View source for International Standard Book Number

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{{Infobox identifier
| name          = International Standard Book Number
| image         = EAN-13-ISBN-13.svg
| image_caption = A 13-digit ISBN, 978-3-16-148410-0, as represented by an [[International Article Number (EAN)|EAN-13 bar code]]
| acronym       = ISBN
| start_date    = {{Start date and age|1970}}
| organisation  = International ISBN Agency
| digits        = 13 (formerly 10)
| check_digit   = Weighted sum
| example       = 978-3-16-148410-0
| website       = {{URL|www.isbn-international.org}}
}}
The '''International Standard Book Number''' ('''ISBN''') is a unique{{efn|Occasionally, publishers erroneously assign an ISBN to more than one title—the first edition of ''[[The Ultimate Alphabet]]'' and ''The Ultimate Alphabet Workbook'' have the same ISBN, 0-8050-0076-3. Conversely, books are published with several ISBNs: A German second-language edition of ''[[Emil und die Detektive]]'' has the ISBNs 87-23-90157-8 (Denmark), 0-8219-1069-8 (United States), 91-21-15628-X (Sweden), 0-85048-548-7 (United Kingdom) and 3-12-675495-3 (Germany).}}{{efn|In some cases, books sold only as sets share ISBNs. For example, the [[Vance Integral Edition]] used only two ISBNs for 44 books.}} numeric commercial book identifier.

An ISBN is assigned to each edition and variation (except reprintings) of a book. For example, an [[e-book]], a [[paperback]] and a [[hardcover]] edition of the same book would each have a different ISBN. The ISBN is 13 digits long if assigned on or after 1 January 2007, and 10 digits long if assigned before 2007. The method of assigning an ISBN is nation-based and varies from country to country, often depending on how large the publishing industry is within a country.

The initial ISBN configuration of recognition{{clarify|date=October 2017|reason=What is a "configuration of recognition", and what does it mean to generate it?}} was generated in 1967 based upon the 9-digit '''Standard Book Numbering''' ('''SBN''') created in 1966. The 10-digit ISBN format was developed by the [[International Organization for Standardization]] (ISO) and was published in 1970 as international standard ISO 2108 (the SBN code can be converted to a ten digit ISBN by prefixing it with a zero).

A book can be printed without a printed ISBN if it is printed privately or the author does not follow the usual ISBN procedure; however, this can be rectified later.<ref>Bradley, Philip (1992). {{cite web|url= http://www.theindexer.org/files/18-1/18-1_025.pdf |title=Book numbering: The importance of the ISBN }}&nbsp;{{small|(245KB)}}. ''The Indexer.'' '''18''' (1): 25–26.</ref>

Another identifier, the [[International Standard Serial Number]] (ISSN), identifies periodical publications such as [[magazine]]s; and the [[International Standard Music Number]] (ISMN) covers for musical scores.

== History ==
The Standard Book Numbering (SBN) [[code]] is a 9-digit commercial [[book]] [[identifier]] system created by [[Gordon Foster]],  Emeritus Professor of Statistics at [[Trinity College, Dublin]],<ref name="From Archive.org-4646971">{{cite web |url=http://www.informaticsdevelopmentinstitute.net/isbn.html |title=INTERNATIONAL STANDARD BOOK NUMBERING (ISBN) SYSTEM original 1966 report |work=informaticsdevelopmentinstitute.net |date=1966 |accessdate=20 April 2014 |archiveurl=https://web.archive.org/web/20110430024722/http://www.informaticsdevelopmentinstitute.net/isbn.html |archivedate=30 April 2011 |deadurl=yes |first=Gordon |last=Foster}}</ref> for the booksellers and stationers [[WHSmith]] and others in 1965.<ref name="history">{{cite web|url=http://www.isbn.org/ISBN_history |title=ISBN History |work=isbn.org |date=20 April 2014 |accessdate=20 April 2014 |author= |archiveurl=https://web.archive.org/web/20140420232459/http://www.isbn.org/ISBN_history |archivedate=20 April 2014 |deadurl=no |df=dmy-all }}</ref> The ISBN configuration of recognition was generated in 1967 in the United Kingdom by David Whitaker<ref name="ktieb">{{cite book|title=Manwal ghall-Utenti tal-ISBN|url=http://ktieb.org.mt/wp-content/uploads/2016/02/Manwal-ghall-Utenti-tal-ISBN-Maltese.pdf|publisher=Kunsill Nazzjonali tal-Ktieb|edition=6th|language=Maltese|location=[[Malta]]|date=2016|archiveurl=https://web.archive.org/web/20160817083617/http://ktieb.org.mt/wp-content/uploads/2016/02/Manwal-ghall-Utenti-tal-ISBN-Maltese.pdf|archivedate=17 August 2016|page=5|isbn=978-99957-889-4-0}}</ref> (regarded as the "Father of the ISBN"<ref name="niso.org">{{citation | format = PDF | url = http://www.niso.org/apps/group_public/download.php/6294/ISQ_vol8_no3_July1996.pdf | title = Information Standards Quarterly | date = July 1996 | page = 12 | number = 3 | volume = 8 | publisher = ISO}}</ref>) and in 1968 in the US by Emery Koltay<ref name="ktieb"/> (who later became director of the U.S. ISBN agency [[R.R. Bowker]]).<ref name="niso.org" /><ref>{{cite web|author=US ISBN Agency |url=http://commerce.bowker.com/standards/home/isbn/about_information_standards.asp |title=Bowker.com – Products |publisher=Commerce.bowker.com |date= |accessdate=2015-06-11}}</ref><ref>{{cite web|first=Daniel|last=Gregory |url=http://www.printrs.com/isbn.htm |title=ISBN |publisher=PrintRS |date= |accessdate=2015-06-11}}</ref>

The 10-digit ISBN format was developed by the [[International Organization for Standardization]] (ISO) and was published in 1970 as international standard ISO 2108.<ref name="history" /><ref name="ktieb"/> The United Kingdom continued to use the 9-digit SBN code until 1974.  ISO has appointed the International ISBN Agency as the registration authority for ISBN worldwide and the ISBN Standard is developed under the control of ISO Technical Committee 46/Subcommittee 9 [[TC 46/SC 9]].  The [[International Organization for Standardization|ISO]] on-line facility only refers back to 1978.<ref>{{citation | format = PDF | url = http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=6897 | title = ISO 2108:1978 | publisher = ISO}}</ref>

An SBN may be converted to an ISBN by prefixing the digit "0".  For example, the second edition of ''[[Mr. J. G. Reeder Returns]]'', published by Hodder in 1965, has {{Nowrap|"SBN 340 01381 8"}} – 340 indicating the publisher, 01381 their serial number, and 8 being the check digit. This can be converted to {{ISBN|0-340-01381-8}}; the check digit does not need to be re-calculated.

Since 1 January 2007, ISBNs have contained 13 digits, a format that is compatible with "[[Bookland]]" European Article Number [[European Article Number|EAN]]-13s.<ref>{{citation | url = http://www.lac-bac.gc.ca/iso/tc46sc9/isbn.htm | title = Frequently Asked Questions about the new ISBN standard from ISO | author = TC 46/SC 9 | publisher = LAC‐BAC | place = CA}}</ref>

== Overview ==
An ISBN is assigned to each edition and variation (except reprintings) of a book. For example, an ebook, a paperback, and a hardcover edition of the same book would each have a different ISBN.<ref>{{cite web|url= https://www.isbn-international.org/sites/default/files/ISBN%20Manual%202012%20-corr.pdf |title=See paragraph 5.2 of ISBN Users' Manual International edition (2012) }}&nbsp;{{small|(548&nbsp;KB)}}</ref> The ISBN is 13 digits long if assigned on or after 1 January 2007, and 10 digits long if assigned before 2007. An International Standard Book Number consists of 4 parts (if it is a 10 digit ISBN) or 5 parts (for a 13 digit ISBN):

[[File:ISBN Details.svg|thumb|The parts of a 10-digit ISBN and the corresponding EAN‑13 and barcode. Note the different check digits in each. The part of the EAN‑13 labeled "EAN" is the [[Bookland]] country code.]]

# for a 13-digit ISBN, a prefix element – a ''[[GS1]] prefix'': so far 978 or 979 have been made available by GS1,<ref name="ISBN User Man" />
# the ''registration group element'' (language-sharing country group, individual country or territory),<ref>Some books have several codes in the first block: e.g. A. M. Yaglom's ''Correlation Theory...'', published by [[Springer Verlag]], has two ISBNs, 0-387-96331-6 and 3-540-96331-6. Though Springer's 387 and 540 codes are different for English (0) and German (3); the same item number 96331 produces the same check digit: 6. Springer uses 431 as their publisher code for Japanese (4) and 4-431-96331-? would also have check digit ? = 6.  Other Springer books in English have publisher code 817, and 0-817-96331-? would also get check digit ? = 6. This suggests special considerations were made for assigning Springer's publisher codes, as random assignments of different publisher codes would ''not'' lead the same item number to get the same check digit every time. Finding publisher codes for English and German, say, with this effect amounts to solving a linear equation in modular arithmetic.</ref>
# the ''registrant'' element,
# the ''publication element'',<ref name="ISBN User Man" /> and
# a ''[[checksum]] character'' or [[check digit]].<ref name="ISBN User Man" />

A 13-digit ISBN can be separated into its parts (''prefix element'', ''registration group'', ''registrant'', ''publication'' and ''check digit''), and when this is done it is customary to separate the parts with [[hyphen]]s or spaces.  Separating the parts (''registration group'', ''registrant'', ''publication'' and ''check digit'') of a 10-digit ISBN is also done with either hyphens or spaces.  Figuring out how to correctly separate a given ISBN is complicated, because most of the parts do not use a fixed number of digits.<ref>The International ISBN agency's ''ISBN User's Manual'' says: "The ten-digit number is divided into four parts of variable length, which must be separated clearly, by hyphens or spaces" although omission of separators is permitted for internal data processing. If present, hyphens must be correctly placed; see [https://www.isbn-international.org/range_file_generation ISBN hyphenation definition]. The actual definition for hyphenation contains more than 220 different registration group elements with each one broken down into a few to several ranges for the length of the registrant element (more than 1,000 total). The document defining the ranges, listed by agency, is 29 pages.</ref>

=== How ISBNs are issued ===
ISBN issuance is country-specific, in that ISBNs are issued by the ISBN registration agency that is responsible for that country or territory regardless of the publication language. The ranges of ISBNs assigned to any particular country are based on the publishing profile of the country concerned, and so the ranges will vary depending on the number of books and the number, type, and size of publishers that are active. Some ISBN registration agencies are based in national libraries or within ministries of culture and thus may receive direct funding from government to support their services. In other cases, the ISBN registration service is provided by organisations such as bibliographic data providers that are not government funded. In Canada, ISBNs are issued at no cost with the stated purpose of encouraging Canadian culture.<ref>{{Cite web|title = ISBN Canada|url = http://www.bac-lac.gc.ca/eng/services/isbn-canada/Pages/isbn-canada.aspx|website = www.bac-lac.gc.ca|access-date = 2016-01-19|first = Library and Archives|last = Canada}}</ref> In the United Kingdom, United States, and some other countries, where the service is provided by non-government-funded organisations, the issuing of ISBNs requires payment of a fee.

'''Australia:''' ISBNs are issued by the commercial library services agency Thorpe-Bowker,<ref>{{cite web|url=https://www.myidentifiers.com.au/isbn/US_isbn_agency|title=About the U.S. ISBN Agency|publisher=}}</ref> and prices range from $42 for a single ISBN (plus a $55 registration fee for new publishers) to $2,890 for a block of 1,000 ISBNs. Access is immediate when requested via their website.<ref>{{cite web
  | title = Bowker -- ISBN
  | publisher = Thorpe-Bowker  | date = 5 Jan 2009
  | url = https://www.myidentifiers.com.au/isbn/main
  | accessdate = 29 March 2012}}</ref>

'''Brazil:''' [[National Library of Brazil]], a government agency, is responsible for issuing ISBNs, and there is a cost of R$16 <ref name="ISBN BR">{{cite web|url=http://www.isbn.bn.br/website/tabela-de-precos|title=TABELA DE PREÇOS DOS SERVIÇOS|publisher=Biblioteca Nacional, Government of Brazil|accessdate=8 September 2015}}</ref>

'''Canada:''' [[Library and Archives Canada]], a government agency, is responsible for issuing ISBNs, and there is no cost. Works in French are issued an ISBN by the [[Bibliothèque et Archives nationales du Québec]].

'''Colombia:''' [[Cámara Colombiana del Libro]], a NGO, is responsible for issuing ISBNs. Cost of issuing an ISBN is about USD 20.

'''Hong Kong:''' The Books Registration Office (BRO), under the Hong Kong Public Libraries, issues ISBNs in Hong Kong. There is no fee.<ref>{{cite web|title=Introduction to Books Registration|url=https://www.hkpl.gov.hk/en/about-us/services/book-registration/introduction.html|publisher=Hong Kong Public Libraries|accessdate=12 January 2017}}</ref>

'''India:''' The Raja Rammohun Roy National Agency for ISBN (Book Promotion and Copyright Division), under Department of Higher Education, a constituent of the [[Ministry of Human Resource Development]], is responsible for registration of Indian publishers, authors, universities, institutions, and government departments that are responsible for publishing books.<ref>{{Cite web|url=http://pib.nic.in/newsite/PrintRelease.aspx?relid=138686|title=Union HRD Minister Smt. Smriti Zubin Irani Launches ISBN Portal|last=|first=|date=|website=|publisher=|access-date=}}</ref> There is no fee associated in getting ISBN in India.<ref>{{Cite web|url=http://www.24by7publishing.com/isbn-for-self-publishers---independent-authors-in-india.html|title=How to get ISBN in India|last=|first=|date=|website=|publisher=|access-date=}}</ref>

'''Italy:''' The privately held company ''EDISER srl'', owned by ''Associazione Italiana Editori'' (Italian Publishers Association) is responsible for issuing ISBNs.<ref>{{cite web | url = http://www.isbn.it/LAGENZIA.aspx | title = ISBN – Chi siamo e contatti | publisher = EDISER srl | accessdate = 3 January 2015 | language = italian | trans-title = ISBN – Who we are and contacts }}</ref> The original national prefix 978-88 is reserved for publishing companies, starting at €49 for a ten-codes block<ref name="ediser-tariffs">{{cite web | url = http://www.isbn.it/TARIFFE.aspx | title = ISBN – Tariffe Servizi ISBN | publisher = EDISER srl | accessdate = 3 January 2015 | language = italian | trans-title = ISBN Service Tariffs}}</ref> while a new prefix 979-12 is dedicated to self-publishing authors, at a fixed price of €25 for a single code.

'''Maldives:''' The [[National Bureau of Classification (NBC)]] is responsible for ISBN registrations for publishers who are publishing in the Maldives.{{citation needed|date=June 2016}}

'''Malta:''' The National Book Council ({{lang-mt|Il-Kunsill Nazzjonali tal-Ktieb}}) issues ISBN registrations in [[Malta]].<ref>{{cite web|title=ISBN|url=http://ktieb.org.mt/?page_id=22|date=2016|publisher=Kunsill Nazzjonali tal-Ktieb|archiveurl=https://web.archive.org/web/20161023123140/http://ktieb.org.mt/?page_id=22|archivedate=23 October 2016}}</ref><ref>{{cite book|title=Manwal ghall-Utenti tal-ISBN|url=http://ktieb.org.mt/wp-content/uploads/2016/02/Manwal-ghall-Utenti-tal-ISBN-Maltese.pdf|publisher=Kunsill Nazzjonali tal-Ktieb|language=Maltese|location=[[Malta]]|edition=6th|date=2016|archiveurl=https://web.archive.org/web/20160817083617/http://ktieb.org.mt/wp-content/uploads/2016/02/Manwal-ghall-Utenti-tal-ISBN-Maltese.pdf|archivedate=17 August 2016|pages=1–40|isbn=978-99957-889-4-0}}</ref><ref>{{cite web|title=Gazzetta tal-Gvern ta' Malta|url=https://govcms.gov.mt/en/Government/Government%20Gazette/Documents/2015/01/Government%20Gazette%20-%2023%20January.pdf|publisher=Government Gazette|date=23 January 2015|page=582|archiveurl=https://web.archive.org/web/20161123220053/https://govcms.gov.mt/en/Government/Government%20Gazette/Documents/2015/01/Government%20Gazette%20-%2023%20January.pdf|archivedate=23 November 2016}}</ref>

'''Morocco:''' The National Library of Morocco is responsible for ISBN registrations for publishing in [[Morocco]] and [[Southern Provinces|Moroccan-occupied portion of Western Sahara]].

'''New Zealand:''' The [[National Library of New Zealand]] is responsible for ISBN registrations for publishers who are publishing in New Zealand.<ref name=NLNZ>{{cite web|title=ISBNs, ISSNs, and ISMNs|url=http://natlib.govt.nz/publishers-and-authors/isbns-issns-and-ismns|website=National Library of New Zealand|publisher=New Zealand Government|accessdate=19 January 2016}}</ref>

'''Pakistan:''' The [[National Library of Pakistan]] is responsible for ISBN registrations for Pakistani publishers, authors, universities, institutions, and government departments that are responsible for publishing books.

'''South Africa:''' The [[National Library of South Africa]] is responsible for ISBN issuance for South African publishing institutions and authors.

'''United Kingdom and Republic of Ireland:''' The privately held company ''Nielsen Book Services Ltd'', part of [[Nielsen Holdings]] N.V., is responsible for issuing ISBNs in blocks of 10, 100 or 1000. Prices start from £120 (plus [[VAT]]) for the smallest block on a standard turnaround of ten days.<ref>{{cite web | url = http://www.isbn.nielsenbook.co.uk/controller.php?page=123 | title = Nielsen UK ISBN Agency | publisher = Nielsen UK ISBN Agency | accessdate = 2 January 2015}}</ref>

'''United States:''' In the United States, the privately held company [[R.R. Bowker]] issues ISBNs.<ref name="ktieb"/> There is a charge that varies depending upon the number of ISBNs purchased, with prices starting at $125 for a single number. Access is immediate when requested via their website.<ref>{{cite web
  | title = Bowker -- ISBN
  | date = 8 March 2013
  | publisher = RR Bowker
  | url = http://www.bowker.com/en-US/products/servident_isbn.shtml
  | accessdate = 8 March 2013}}</ref>

Publishers and authors in other countries obtain ISBNs from their respective national ISBN registration agency. A directory of ISBN agencies is available on the [[International ISBN Agency]] website.

=== Registration group identifier ===
{{anchor|Registration Group identifier}}
The [[list of ISBN identifier groups|registration group identifier]] is a 1- to 5-digit number that is valid within a single prefix element (i.e. one of 978 or 979).<ref name="ISBN User Man" /> Registration group identifiers have primarily been allocated within the 978 prefix element.<ref name="ISBN Ranges">{{cite web|url=https://www.isbn-international.org/range_file_generation# |title=ISBN Ranges |work=isbn-international.org |at=Select the format you desire and click on the Generate button |date=29 April 2014 |accessdate=29 April 2014 |author= |archiveurl=https://web.archive.org/web/20140429101326/https://www.isbn-international.org/range_file_generation |archivedate=29 April 2014 |deadurl=no |df=dmy-all }}</ref> The single-digit group identifiers within the 978 prefix element are: 0 or 1 for English-speaking countries; 2 for French-speaking countries; 3 for German-speaking countries; 4 for Japan; 5 for Russian-speaking countries; and 7 for People's Republic of China. An example 5-digit group identifier is 99936, for [[Bhutan]]. The allocated group IDs are: 0–5, 600–621, 7, 80–94, 950–989, 9926–9989, and 99901–99976.<ref>See [https://www.isbn-international.org/range_file_generation a complete list of group identifiers].  ISBN.org sometimes calls them ''group numbers''. Their table of identifiers now refers to ''ISBN prefix ranges'', which must be assumed to be group identifier ranges.</ref>  Books published in rare languages typically have longer group identifiers.<ref>{{cite book |last=Hailman |first=Jack Parker |date=2008 |title=Coding and redundancy: man-made and animal-evolved signals |publisher=Harvard University Press |page=209 |isbn=978-0-674-02795-4}}</ref>

Within the 979 prefix element, the registration group identifier 0 is reserved for compatibility with [[International Standard Music Number]]s (ISMNs), but such material is not actually assigned an ISBN.<ref name="ISBN User Man">{{cite book|url=https://www.isbn-international.org/sites/default/files/ISBN%20Manual%202012%20-corr.pdf |title=ISBN Users' manual |work=isbn-international.org |edition=Sixth International |isbn=978-92-95055-02-5 |date=2012 |accessdate=29 April 2014 |author=International ISBN Agency |archiveurl=https://web.archive.org/web/20140429101742/https://www.isbn-international.org/sites/default/files/ISBN%20Manual%202012%20-corr.pdf |archivedate=29 April 2014 |deadurl=no |pages=7, 23 |df=dmy-all }}</ref> The registration group identifiers within prefix element 979 that have been assigned are 10 for France, 11 for the Republic of Korea, and 12 for Italy.<ref name="C4WDefault-5691881">{{cite web |url=https://www.isbn-international.org/export_rangemessagebyprefix.pdf |title=International ISBN Agency – Range Message (pdf sorted by prefix) |page=29 |work=isbn-international.org |date=5 December 2014 |accessdate=15 December 2014 |author=International ISBN Agency}}</ref>

The original 9-digit standard book number (SBN) had no registration group identifier, but prefixing a zero (0) to a 9-digit SBN creates a valid 10-digit ISBN.

=== Registrant element ===
The national ISBN agency assigns the registrant element ([[cf.]] [[:Category:ISBN agencies]]) and an accompanying series of ISBNs within that registrant element to the publisher; the publisher then allocates one of the ISBNs to each of its books. In most countries, a book publisher is not required by law to assign an ISBN; however, most bookstores only handle ISBN bearing publications.{{citation needed|date=August 2014}}

A listing of more than 900,000 assigned publisher codes is published, and can be ordered in book form ([[Euro|€]]1399, [[United States dollar|US$]]1959). The web site of the ISBN agency does not offer any free method of looking up publisher codes.<ref>See [http://www.isbn-international.org/page/directory Publisher's International ISBN Directory]</ref> Partial lists have been compiled (from library catalogs) for the English-language groups: [[List of group-0 ISBN publisher codes|identifier 0]] and [[List of group-1 ISBN publisher codes|identifier 1]].

Publishers receive blocks of ISBNs, with larger blocks allotted to publishers expecting to need them; a small publisher may receive ISBNs of one or more digits for the registration group identifier, several digits for the registrant, and a single digit for the publication element. Once that block of ISBNs is used, the publisher may receive another block of ISBNs, with a different registrant element. Consequently, a publisher may have different allotted registrant elements. There also may be more than one registration group identifier used in a country. This might occur once all the registrant elements from a particular registration group have been allocated to publishers.

By using variable block lengths, registration agencies are able to customise the allocations of ISBNs that they make to publishers. For example, a large publisher may be given a block of ISBNs where fewer digits are allocated for the registrant element and many digits are allocated for the publication element; likewise, countries publishing many titles have few allocated digits for the registration group identifier and many for the registrant and publication elements.<ref>{{Cite book|title=The Book Book: A Complete Guide to Creating a Book on Your Computer|last=Splane|first=Lily|publisher=Anaphase II Publishing|year=2002|isbn=978-0-945962-14-4|location=|pages=37|quote=|via=}}</ref> Here are some sample <nowiki>ISBN-10</nowiki> codes, illustrating block length variations.
{| class="wikitable" style="width:100%; max-width:40em;"
|-
! ISBN || Country or area || Publisher
|-
| <tt>99921-58-10-7</tt><!--ISBN-13: 978-99921-58-10-4--> || Qatar || NCCAH, Doha
|-
| <tt>9971-5-0210-0</tt><!--ISBN-13: 978-9971-5-0210-2--> || Singapore || World Scientific
|-
| <tt>960-425-059-0</tt><!--ISBN-13: 978-960-425-059-2--> || Greece || Sigma Publications
|-
| <tt>80-902734-1-6</tt><!--ISBN-13: 978-80-902734-1-2--> || Czech Republic; Slovakia || Taita Publishers
|-
| <tt>85-359-0277-5</tt><!--ISBN-13: 978-80-902734-1-2--> || Brazil || Companhia das Letras
|-
| <tt>1-84356-028-3</tt><!--ISBN-13: 978-0-14-015098-8--> || English-speaking area || Simon Wallenberg Press
|-
| <tt>0-684-84328-5</tt><!--ISBN-13: 978-0-684-84328-5--> || English-speaking area || Scribner
|-
| <tt>0-8044-2957-X</tt><!--ISBN-13: 978-0-8044-2957-3--> || English-speaking area || Frederick Ungar
|-
| <tt>0-85131-041-9</tt><!--ISBN-13: 978-0-85131-041-1--> || English-speaking area || J. A. Allen & Co.
|-
| <tt>0-943396-04-2</tt><!--ISBN-13: 978-0-943396-04-0--> || English-speaking area || Willmann–Bell
|-
| <tt>0-9752298-0-X</tt><!--ISBN-13: 978-0-9752298-0-4--> || English-speaking area || KT Publishing
|}

==== Pattern for English language ISBNs ====
English-language registration group elements are 0 and 1 (2 of more than 220 registration group elements). These two registration group elements are divided into registrant elements in a systematic pattern, which allows their length to be determined, as follows:<ref name="C4WDefault-9122662">{{cite web |url=https://www.isbn-international.org/range_file_generation# |title=ISBN Ranges |date=15 September 2014 <!-- No date available; last modification date used. --> |accessdate=15 September 2014 |work=isbn-international.org |author1=<!--Staff writer(s); no by-line.--> |publisher=International ISBN Agency}}</ref>

{| class="wikitable" style="text-align:right;"
|-
! rowspan="2" | Publication<br />element length
! colspan="3" | 0 – Registration group element
! colspan="3" | 1 – Registration group element
! rowspan="2" | Total<br />Registrants
|-
! From !! To !! Registrants !! From !! To !! Registrants
|-
! 6 digits
| style="font-family:monospace;" | 0-00-xxxxxx-x
| style="font-family:monospace;" | 0-19-xxxxxx-x
| 20
| style="font-family:monospace;" | 1-00-xxxxxx-x
| style="font-family:monospace;" | 1-09-xxxxxx-x
| 10
| 30
|-
! 5 digits
| style="font-family:monospace;" | 0-200-xxxxx-x
| style="font-family:monospace;" | 0-699-xxxxx-x
| 500
| style="font-family:monospace;" | 1-100-xxxxx-x
| style="font-family:monospace;" | 1-399-xxxxx-x
| 300
| 800
|-
! 4 digits
| style="font-family:monospace;" | 0-7000-xxxx-x
| style="font-family:monospace;" | 0-8499-xxxx-x
| 1,500
| style="font-family:monospace;" | 1-4000-xxxx-x
| style="font-family:monospace;" | 1-5499-xxxx-x
| 1,500
| 3,000
|-
! 3 digits
| style="font-family:monospace;" | 0-85000-xxx-x
| style="font-family:monospace;" | 0-89999-xxx-x
| 5,000
| style="font-family:monospace;" | 1-55000-xxx-x
| style="font-family:monospace;" | 1-86979-xxx-x
| 31,980
| 36,980
|-
! 2 digits
| style="font-family:monospace;" | 0-900000-xx-x
| style="font-family:monospace;" | 0-949999-xx-x
| 50,000
| style="font-family:monospace;" | 1-869800-xx-x
| style="font-family:monospace;" | 1-998999-xx-x
| 129,200
| 179,200
|-
! 1 digit
| style="font-family:monospace;" | 0-9500000-x-x
| style="font-family:monospace;" | 0-9999999-x-x
| 500,000
| style="font-family:monospace;" | 1-9990000-x-x
| style="font-family:monospace;" | 1-9999999-x-x
| 10,000
| 510,000
|-
! colspan="3" style="text-align:right;" | Total
| 557,020
! colspan="2" style="text-align:right;" | Total
| 172,990
| 730,010
|}

== Check digits ==
A [[check digit]] is a form of redundancy check used for [[error detection]], the decimal equivalent of a binary [[check bit]].  It consists of a single digit computed from the other digits in the number.  The method for the ten digit code is an extension of that for SBNs, the two systems are compatible, and SBN prefixed with "0" will give the same check-digit as without – the digit is base eleven, and can be 0-9 or X.  The system for thirteen digit codes is not compatible and will, in general, give a different check digit from the corresponding 10 digit ISBN, and does not provide the same protection against transposition.  This is because the thirteen digit code was required to be compatible with the EAN format, and hence could not contain an "X".

=== ISBN-10 check digits ===
The 2001 edition of the official manual of the [http://www.isbn-international.org/ International ISBN Agency] says that the <nowiki>ISBN-10</nowiki> [[check digit]]<ref>{{cite web|url=http://www.isbn.org/standards/home/isbn/international/html/usm4.htm |title=ISBN Users' Manual – 4. Structure of ISBN |publisher=Isbn.org |accessdate=2013-05-27 |deadurl=yes |archiveurl=https://web.archive.org/web/20130522043458/http://www.isbn.org/standards/home/isbn/international/html/usm4.htm |archivedate=22 May 2013 }}</ref> – which is the last digit of the ten-digit ISBN – must range from 0 to 10 (the symbol X is used for 10), and must be such that the sum of all the ten digits, each multiplied by its (integer) weight, descending from 10 to 1, is a multiple of [[11 (number)|11]].

For example, for an <nowiki>ISBN-10</nowiki> of 0-306-40615-2:
:<math>
\begin{align}
 s &= (0\times 10) + (3\times 9) + (0\times 8) + (6\times 7) + (4\times 6) + (0\times 5) + (6\times 4) + (1\times 3) + (5\times 2) + (2\times 1) \\
   &=    0 + 27 +   0 +  42 +  24 +   0 + 24  +   3 + 10 + 2\\
   &= 132 = 12\times 11
\end{align}
</math>

Formally, using [[modular arithmetic]], we can say:
:<math>(10x_1+9x_2+8x_3+7x_4+6x_5+5x_6+4x_7+3x_8+2x_9+x_{10})\equiv 0 \pmod{11}.</math>

It is also true for <nowiki>ISBN-10</nowiki>'s that the sum of all the ten digits, each multiplied by its weight in ''ascending'' order from 1 to 10, is a multiple of 11. For this example:
:<math>
\begin{align}
 s &= (0\times 1) + (3\times 2) + (0\times 3) + (6\times 4) + (4\times 5) + (0\times 6) + (6\times 7) + (1\times 8) + (5\times 9) + (2\times 10) \\
   &=    0 + 6 +   0 +  24 +  20 +   0 + 42  +   8 + 45 + 20\\
   &= 165 = 15\times 11
\end{align}
</math>

Formally, we can say:
:<math>(x_1 + 2x_2 + 3x_3 + 4x_4 + 5x_5 + 6x_6 + 7x_7 + 8x_8 + 9x_9 + 10x_{10})\equiv 0 \pmod{11}.</math>

The two most common errors in handling an ISBN (e.g., typing or writing it) are a single altered digit or the transposition of adjacent digits. It can be [[mathematical proof|proved]] that all possible valid <nowiki>ISBN-10</nowiki>'s have at least two digits different from each other. It can also be proved that there are no pairs of valid <nowiki>ISBN-10</nowiki>'s with eight identical digits and two transposed digits. (These are true only because the ISBN is less than 11 digits long, and because 11 is a [[prime number]].)
The ISBN check digit method therefore ensures that it will always be possible to detect these two most common types of error, i.e. if either of these types of error has occurred, the result will never be a valid ISBN&nbsp;– the sum of the digits multiplied by their weights will never be a multiple of 11. However, if the error occurs in the publishing house and goes undetected, the book will be issued with an invalid ISBN.<ref>For example, ''I'saka: a sketch grammar of a language of north-central New Guinea.'' Pacific Linguistics. ISBN "0-85883-554-4".</ref>

In contrast, it is possible for other types of error, such as two altered non-transposed digits, or three altered digits, to result in a valid ISBN (although it is still unlikely).

=== ISBN-10 check digit calculation ===
<!-- "Damm algorithm" links here -->
Each of the first nine digits of the ten-digit ISBN—excluding the check digit itself—is multiplied by its (integer) weight, descending from 10 to 2, and the sum of these nine products found. The value of the check digit is simply the one number between 0 and 10 which, when added to this sum, means the total is a multiple of 11. 

For example, the check digit for an <nowiki>ISBN-10</nowiki> of 0-306-40615-''?'' is calculated as follows:
:<math>
\begin{align}
 s &= (0\times 10)+(3\times 9)+(0\times 8)+(6\times 7)+(4\times 6)+(0\times 5)+(6\times 4)+(1\times 3)+(5\times 2)\\
   &= 130
\end{align}
</math>
Adding 2 to 130 gives a multiple of 11 (132 = 12 x 11) &minus; this is the only number between 0 and 10 which does so. Therefore the check digit has to be 2, and the complete sequence is <nowiki>ISBN 0-306-40615-2</nowiki>. The value <math>x_{10}</math> required to satisfy this condition might be 10; if so, an 'X' should be used.

Alternatively, [[modular arithmetic]] is convenient for calculating the check digit using modulus 11. The [[remainder]] of this sum when it is divided by 11 (i.e. its value modulo 11), is computed. This remainder plus the check digit must equal either 0 or 11. Therefore, the check digit is (11 minus the remainder of the sum of the products modulo 11) modulo 11. Taking the remainder modulo 11 a second time accounts for the possibility that the first remainder is 0. Without the second modulo operation the calculation could end up with 11 – 0 = 11 which is invalid. (Strictly speaking the ''first'' "modulo 11" is unneeded, but it may be considered to simplify the calculation.)

For example, the check digit for the <nowiki>ISBN-10</nowiki> of 0-306-40615-''?'' is calculated as follows:
:<math>
\begin{align}
 s &= (11 - ( ((0\times 10)+(3\times 9)+(0\times 8)+(6\times 7)+(4\times 6)+(0\times 5)+(6\times 4)+(1\times 3)+(5\times 2) ) \,\bmod\, 11 ) \,\bmod\, 11\\
   &=    (11 - (0 + 27 +   0 +  42 +  24 +   0 + 24  +   3 + 10 ) \,\bmod\, 11) \,\bmod\, 11\\
   &= (11-(130 \,\bmod\, 11))\,\bmod\, 11 \\
   &= (11-(9))\,\bmod\, 11 \\
   &= (2)\,\bmod\, 11 \\
   &= 2
\end{align}
</math>

Thus the check digit is 2.

It is possible to avoid the multiplications in a software implementation by using two accumulators.  Repeatedly adding <code>t</code> into <code>s</code> computes the necessary multiples:
<source lang="C">
// Returns ISBN error syndrome, zero for a valid ISBN, non-zero for an invalid one.
// digits[i] must be between 0 and 10.
int CheckISBN(int const digits[10])
{
        int i, s = 0, t = 0;

        for (i = 0; i < 10; i++) {
                t += digits[i];
                s += t;
        }
        return s % 11;
}
</source>
The modular reduction can be done once at the end, as shown above (in which case <code>s</code> could hold a value as large as 496, for the invalid <nowiki>ISBN 99999-999-9-X</nowiki>), or <code>s</code> and <code>t</code> could be reduced by a conditional subtract after each addition.

=== ISBN-13 check digit calculation ===
The 2005 edition of the International ISBN Agency's official manual<ref>{{cite web|url=https://www.isbn-international.org/sites/default/files/ISBN%20Manual%202012%20-corr.pdf |title=ISBN Users' Manual International edition (2012) |deadurl=yes |archiveurl=https://web.archive.org/web/20140429101742/https://www.isbn-international.org/sites/default/files/ISBN%20Manual%202012%20-corr.pdf |archivedate=29 April 2014 |df=dmy-all }}&nbsp;{{small|(284&nbsp;KB)}}</ref> describes how the 13-digit ISBN [[check digit]] is calculated. The <nowiki>ISBN-13</nowiki> check digit, which is the last digit of the ISBN, must range from 0 to 9 and must be such that the sum of all the thirteen digits, each multiplied by its (integer) weight, alternating between 1 and 3, is a multiple of [[10 (number)|10]].

Formally, using [[modular arithmetic]], we can say:
:<math>(x_1 + 3x_2 + x_3 + 3x_4 + x_5 + 3x_6 + x_7 + 3x_8 + x_9 + 3x_{10} + x_{11} + 3x_{12} + x_{13} ) \equiv 0 \pmod{10}.</math>

The calculation of an <nowiki>ISBN-13</nowiki> check digit begins with the first 12 digits of the thirteen-digit ISBN (thus excluding the check digit itself). Each digit, from left to right, is alternately multiplied by 1 or 3, then those products are summed [[modular arithmetic|modulo]] 10 to give a value ranging from 0 to 9. Subtracted from 10, that leaves a result from 1 to 10. A zero (0) replaces a ten (10), so, in all cases, a single check digit results.

For example, the <nowiki>ISBN-13</nowiki> check digit of 978-0-306-40615-''?'' is calculated as follows:
<!-- This is what we'd like to do, but it is far too wide.
:<math>\textstyle \begin{array}{rlllllllllllll}
s &{}= 1 \times 9 &{}+ 3 \times 7 &{}+ 1 \times 8 &{}+ 3 \times 0 &{}+ 1 \times 3 &{}+ 3 \times 0 &{}+ 1 \times 6 &{}+ 3 \times 4 &{}+ 1 \times 0 &{}+ 3 \times 6 &{}+ 1 \times 1 &{}+ 3 \times 5 \\
 &{}= 9 &{}+21 &{}+ 8 &{}+ 0 &{}+ 3 &{}+ 0 &{}+ 6 &{}+ 12 &{}+ 0 &{}+ 18 &{}+ 1 &{}+ 15 \\
 &{}= 93
\end{array}</math>
-->
 s = 9×1 + 7×3 + 8×1 + 0×3 + 3×1 + 0×3 + 6×1 + 4×3 + 0×1 + 6×3 + 1×1 + 5×3
   =   9 +  21 +   8 +   0 +   3 +   0 +   6 +  12 +   0 +  18 +   1 +  15
   = 93
 93 / 10 = 9 remainder 3
 10 –  3 = 7

Thus, the check digit is 7, and the complete sequence is <nowiki>ISBN 978-0-306-40615-7</nowiki>.

In general, the <nowiki>ISBN-13</nowiki> check digit is calculated as follows.

Let 
:<math>r = \big(10 - \big(x_1 + 3x_2 + x_3 + 3x_4 + \cdots + x_{11} + 3x_{12}\big) \,\bmod\, 10\big).</math>

Then 
:<math>x_{13} = \begin{cases} r &\text{ ; } r < 10 \\ 0 &\text{ ; } r = 10 . \end{cases}</math>

This check system&nbsp;– similar to the [[Universal Product Code|UPC]] check digit formula&nbsp;– does not catch all errors of adjacent digit transposition. Specifically, if the difference between two adjacent digits is 5, the check digit will not catch their transposition. For instance, the above example allows this situation with the 6 followed by a 1. The correct order contributes 3×6+1×1 = 19 to the sum; while, if the digits are transposed (1 followed by a 6), the contribution of those two digits will be 3×1+1×6 = 9. However, 19 and 9 are congruent modulo 10, and so produce the same, final result: both ISBNs will have a check digit of 7. The <nowiki>ISBN-10</nowiki> formula uses the [[prime number|prime]] modulus 11 which avoids this blind spot, but requires more than the digits 0-9 to express the check digit.

Additionally, if the sum of the 2nd, 4th, 6th, 8th, 10th, and 12th digits is tripled then added to the remaining digits (1st, 3rd, 5th, 7th, 9th, 11th, and 13th), the total will always be divisible by 10 (i.e., end in 0).

=== ISBN-10 to ISBN-13 conversion ===
The conversion is quite simple as one only needs to prefix "978" to the existing number and calculate the new checksum using the <nowiki>ISBN-13</nowiki> algorithm.

=== {{anchor|Cancelled ISBN}}Errors in usage ===
Publishers and [[library|libraries]] have varied policies about the use of the ISBN check digit. Publishers sometimes fail to check the correspondence of a book title and its ISBN before publishing it; that failure causes book identification problems for libraries, booksellers, and readers.<ref>{{Cite book|title=Book Publishing I|last=Lorimer|first=Rowland|last2=Shoichet|first2=Jillian|last3=Maxwell|first3=John W.|publisher=CCSP Press|year=2005|isbn=978-0-9738727-0-5|location=|pages=299|quote=|via=}}</ref> For example, {{ISBN|0-590-76484-5}} is shared by two books – ''Ninja gaiden® : a novel based on the best-selling game by Tecmo'' (1990) and ''Wacky Laws'' (1997), both published by [[Scholastic Corporation|Scholastic]].

Most libraries and booksellers display the book record for an invalid ISBN issued by the publisher. The [[Library of Congress]] catalogue contains books published with invalid ISBNs, which it usually tags with the phrase "Cancelled ISBN".<ref>[http://www.loc.gov/marc/bibliographic/bd020.html 020 – International Standard Book Number (R) – MARC 21 Bibliographic – Full]. Library of Congress.</ref> However, book-ordering systems such as [[Amazon.com]] will not search for a book if an invalid ISBN is entered to its search engine.{{Citation needed|date=March 2012}} [[OCLC]] often indexes by invalid ISBNs, if the book is indexed in that way by a member library.

=== eISBN ===
Only the term "ISBN" should be used; the terms "eISBN" and "e-ISBN" have historically been sources of confusion and should be avoided. If a book exists in one or more digital ([[e-book]]) formats, each of those formats must have its own ISBN. In other words, each of the three separate [[EPUB]], [[Amazon Kindle]], and [[PDF]] formats of a particular book will have its own specific ISBN. They should not share the ISBN of the paper version, and there is no generic "eISBN" which encompasses all the e-book formats for a title.<ref>{{Cite news|url=http://www.sellbox.com/myth-eisbn-every-ebook-edition-needs-unique-number/|title=The Myth of the eISBN: Why Every eBook Edition Needs a Unique Number – Publishing services for self publishing authors and businesses|date=2013-06-28|newspaper=Publishing services for self publishing authors and businesses|language=en-US|access-date=2017-01-16}}</ref>

== EAN format used in barcodes, and upgrading ==
Currently the [[barcode]]s on a book's back cover (or inside a mass-market [[paperback]] book's front cover) are [[European Article Number|EAN-13]]; they may have a separate barcode encoding five digits for the [[currency]] and the [[recommended retail price]].<ref>{{Citation | title = Frequently asked questions | publisher = ISBN | place = [[United States of America|US]] | date = 12 March 2014 | url = http://www.isbn-us.com/blog/2014/03/12/isbn-information-frequently-asked-questions/}} — including a detailed description of the EAN-13 format.</ref> For 10 digit ISBNs, the number "978", the [[Bookland]] "country code", is prefixed to the ISBN in the barcode data, and the check digit is recalculated according to the EAN13 formula (modulo 10, 1x and 3x weighting on alternate digits).

Partly because of an expected shortage in certain ISBN categories, the [[International Organization for Standardization]] (ISO) decided to migrate to a thirteen-digit ISBN (<nowiki>ISBN-13</nowiki>). The process began 1 January 2005 and was planned to conclude 1 January 2007.<ref>{{Citation | publisher = Collections | contribution-url = http://www.collectionscanada.ca/iso/tc46sc9/isbn.htm | type = FAQ | title = ISO TC49SC9 | contribution = ISBN | place = [[Canada|CA]]}}</ref>  As of 2011, all the 13-digit ISBNs began with 978.  As the 978 ISBN supply is exhausted, the 979 prefix was introduced.  Part of the 979 prefix is reserved for use with the [[Bookland|Musicland]] code for [[Sheet music|musical scores]] with an [[ISMN]]. 10 digit ISMN codes differed visually as they began with an "M" letter; the bar code represents the "M" as a zero (0), and for checksum purposes it counted as a 3. All ISMNs are now 13 digits commencing 979-0; 979-1 to 979-9 will be used by ISBN.

Publisher identification code numbers are unlikely to be the same in the 978 and 979 ISBNs, likewise, there is no guarantee that language area code numbers will be the same.  Moreover, the ten-digit ISBN check digit generally is not the same as the thirteen-digit ISBN check digit.  Because the GTIN-13 is part of the [[Global Trade Item Number]] (GTIN) system (that includes the GTIN-14, the GTIN-12, and the GTIN-8), the 13-digit ISBN falls within the 14-digit data field range.<ref>{{Citation | title = Standards | contribution-url = http://www.isbn.org/standards/home/isbn/transition.asp | contribution = Are You Ready for <nowiki>ISBN-13</nowiki>? | publisher = ISBN}}</ref>

Barcode format compatibility is maintained, because (aside from the group breaks) the <nowiki>ISBN-13</nowiki> barcode format is identical to the EAN barcode format of existing 10-digit ISBNs. So, migration to an EAN-based system allows booksellers the use of a single numbering system for both books and non-book products that is compatible with existing ISBN based data, with only minimal changes to [[information technology]] systems. Hence, many [[bookstore|booksellers]] (e.g., [[Barnes & Noble]]) migrated to EAN barcodes as early as March 2005. Although many American and Canadian booksellers were able to read EAN-13 barcodes before 2005, most general retailers could not read them. The upgrading of the [[Universal Product Code|UPC]] [[barcode system]] to full EAN-13, in 2005, eased migration to the <nowiki>ISBN-13</nowiki> in North America.

== See also ==
* [[Amazon Standard Identification Number|ASIN]] (Amazon Standard Identification Number)
* [[CODEN]] (serial publication identifier currently used by libraries; replaced by the ISSN for new works)
* [[Digital object identifier|DOI]] (Digital Object Identifier)
* [[English Short Title Catalogue|ESTC]] (English Short Title Catalogue)
* [[ETTN]] (Electronic Textbook Track Number)
* [[International Standard Audiovisual Number|ISAN]] (International Standard Audiovisual Number)
* [[International Standard Music Number|ISMN]] (International Standard Music Number)
* [[International Standard Musical Work Code|ISWC]] (International Standard Musical Work Code)
* [[International Standard Recording Code|ISRC]] (International Standard Recording Code)
* [[International Standard Serial Number|ISSN]] (International Standard Serial Number)
* [[International Standard Text Code|ISTC]] (International Standard Text Code)
* [[ISWN]] (International Standard Wine Number)
* [[Library of Congress Control Number|LCCN]] (Library of Congress Control Number)
* [[List of group-0 ISBN publisher codes]]
* [[List of group-1 ISBN publisher codes]]
* [[OCLC]] number (Online Computer Library Center number<ref>{{cite web|url=http://xisbn.worldcat.org/xisbnadmin/xoclcnum/index.htm|title=xISBN (Web service)|last=|first=|date=|website=|publisher=Xisbn.worldcat.org|accessdate=2013-05-27}}</ref>)
* [[Registration authority]]
* [[Book Item and Component Identifier|BICI]] (Book Item and Component Identifier)
* [[Serial Item and Contribution Identifier|SICI]] (Serial Item and Contribution Identifier)
* [[Special:Booksources]], Wikipedia's ISBN search page
* [[VD 16]] (Verzeichnis der im deutschen Sprachbereich erschienenen Drucke des 16. Jahrhunderts)(in English: ''Bibliography of Books Printed in the German Speaking Countries of the Sixteenth Century'')
* [[VD 17]] (Verzeichnis der im deutschen Sprachraum erschienenen Drucke des 17. Jahrhunderts)(in English: ''Bibliography of Books Printed in the German Speaking Countries of the Seventeenth Century'')

== Notes ==
{{notelist}}

== References ==
{{Reflist|30em}}

== External links ==
{{Wikidata property |1=P957}}
{{Wikidata property |1=P212}}
{{sisterlinks|d=Q33057|mw=Manual:ISBN|species=no|voy=no|wikt=ISBN|n=no|q=no|s=no|b=no|v=no|c=Category:ISBN}}
<!-- ============================== NoMoreLinks ===============-->
<!-- DO NOT ADD MORE LINKS TO THIS ARTICLE. WIKIPEDIA IS NOT A COLLECTION OF LINKS -->
<!-- If you think that your link might be useful,  instead of placing it here, put -->
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<!-- ====================================================== -->
* [http://www.iso.org/iso/en/CatalogueDetailPage.CatalogueDetail?CSNUMBER=36563&ICS1=1&ICS2=140&ICS3=20 ISO 2108:2005]
* [https://www.isbn-international.org/ International ISBN Agency]—coordinates and supervises the worldwide use of the ISBN system
** [https://www.isbn-international.org/range_file_generation# Numerical List of Group Identifiers]—List of language/region prefixes
** [http://www.isbn.org/converterpub.asp Free conversion tool: <nowiki>ISBN-10</nowiki> to <nowiki>ISBN-13</nowiki> & <nowiki>ISBN-13</nowiki> to <nowiki>ISBN-10</nowiki>] from the [http://www.isbn.org/ ISBN agency]. Also shows correct hyphenation & verifies if ISBNs are valid or not.
* {{cite web|url= http://isbn-international.org/en/download/implementation-guidelines-04.pdf |title=Implementation guidelines |postscript=none}}&nbsp;{{small|(51.0&nbsp;KB)}} for the 13-digit ISBN code
* {{DMOZ|Reference/Books/|Books}}
* {{cite web|title=Are You Ready for <nowiki>ISBN-13</nowiki>?|url=http://www.isbn.org/standards/home/isbn/transition.asp|publisher=R. R. Bowker LLC}}
* RFC 3187<!-- should be automatically linked by Wikipedia -->—Using International Standard Book Numbers as [[Uniform Resource Name]]s (URN)

{{Audiovisual works|state=uncollapsed}}
{{ISO standards}}
{{Authority control}}


[[Category:Book publishing]]
[[Category:Bookselling]]
[[Category:Book terminology]]
[[Category:Checksum algorithms]]
[[Category:ISO standards]]
[[Category:Unique identifiers]]
[[Category:International Standard Book Number| ]]