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International Standard Book Number
International Standard Book Number
From Wikipedia
From Wikipedia: (wikipedia:International Standard Book Number)
The International Standard Book Number (ISBN) is a unique^{[1]}^{[2]} numeric commercial book identifier based upon the 9digit Standard Book Numbering (SBN) code created by Gordon Foster, Emeritus Professor of Statistics at Trinity College, Dublin,^{[3]} for the booksellers and stationers W. H. Smith and others in 1966.^{[4]}
The 10digit ISBN format was developed by the International Organization for Standardization (ISO) and was published in 1970 as international standard ISO 2108.^{[4]} (However, the 9digit SBN code was used in the United Kingdom until 1974.) Currently, the ISO's TC 46/SC 9 is responsible for the ISBN. The ISO online facility only refers back to 1978.^{[5]}
Since 1 January 2007, ISBNs have contained 13 digits, a format that is compatible with Bookland EAN13s.^{[6]}
Occasionally, a book may appear 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.^{[7]}
A similar numeric identifier, the International Standard Serial Number (ISSN), identifies periodical publications such as magazines.
Overview[edit]
An ISBN is assigned to each edition and variation (except reprintings) of a book.^{[8]} The ISBN is 13 digits long if assigned after January 1, 2007, and 10 digits long if assigned before 2007. An International Standard Book Number consists of 4 or 5 parts:
 for a 13digit ISBN, a GS1 prefix: 978 or 979 (indicating the industry; in this case, 978 denotes book publishing)^{[9]}
 the group identifier, (languagesharing country group)^{[10]}
 the publisher code,^{[11]}
 the item number (title of the book),^{[11]} and
 a checksum character or check digit.^{[11]}
The ISBN separates its parts (group, publisher, title and check digit) with either a hyphen or a space. Other than the check digit, no part of the ISBN will have a fixed number of digits.^{[12]}
ISBN issuance[edit]
International Standard Book Numbers issuance is country specific, and is tailored for each country's national goals. In Canada the stated purpose of issuing International Standard Book Numbers for no cost was to encourage Canadian culture. In the United Kingdom and United States apparently the issuing of International Standard Book Numbers has become a profit center for the companies involved. Whether or not any of the profits accrue to the taxpayers is not known.
Australia: In Australia ISBNs are issued by the commercial library services agency ThorpeBowker, and prices range from $A40 for a single ISBN (plus a $A55 registration fee for new publishers) through to $2,750 for a block of 1,000 ISBNs.^{[13]}
Canada: In Canada Library and Archives Canada, a government agency, is the responsible entity, and there is no cost.
United Kingdom and Ireland: In the United Kingdom and Ireland the privately held company, Nielsen Book Services, part of Nielsen Holdings N.V., is the responsible entity, and there is a charge. ISBNs are sold in lots of ten or more.
United States: In the United States the privately held company R. R. Bowker is the responsible entity, and there is a charge, which varies depending upon the number of ISBNs purchased, with prices ranging from $125.00 for a single number.^{[14]}
Publishers and authors in other countries need to obtain ISBNs from their local ISBN Agency. A directory of ISBN Agencies is available on the International ISBN Agency website.
Group identifier[edit]
The group identifier is a 1 to 5 digit number. The single digit group identifiers are: 0 or 1 for Englishspeaking countries; 2 for Frenchspeaking countries; 3 for Germanspeaking countries; 4 for Japan; 5 for Russianspeaking countries, 7 for People's Republic of China. An example 5 digit group identifier is 99936, for Bhutan. The allocated group IDs are: 0–5, 600–617, 7, 80–94, 950–989, 9927–9989, and 99901–99967.^{[15]} Some catalogs include books that were published with no ISBN but add a nonstandard number with an asyet unallocated 5digit group such as 99985; this practice is not part of the standard. Books published in rare languages typically have longer group identifiers.^{[9]}
The original standard book number (SBN) had no group identifier, but affixing a zero (0) as prefix to a 9digit SBN creates a valid 10digit ISBN. Group identifiers form a prefix code; compare with country calling codes.
Publisher code[edit]
The national ISBN agency assigns the publisher number (cf. the category:ISBN agencies); the publisher selects the item number. Generally, a book publisher is not required to assign an ISBN, nor is it necessary for a book to display its number (except in China; see below). However, most book stores only handle ISBNbearing merchandise.
A listing of all the 628,000 assigned publisher codes is published, and can be ordered in book form (€558, US$915.46). The web site of the ISBN agency does not offer any free method of looking up publisher codes.^{[16]} Partial lists have been compiled (from library catalogs) for the Englishlanguage groups: identifier 0 and 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 group identifier code, several digits for the publisher, and a single digit for the individual items. Once that block of ISBNs is used, the publisher may receive another block of ISBNs, with a different publisher number. Consequently, a publisher may have different allotted publisher numbers. There also may be more than one group identifier used in a country. This might occur if a popular identifier has used up all of its numbers. The cited list of identifiers shows this has happened in China and in more than a dozen other countries.
By using variable block lengths, a large publisher will have few digits allocated for the publisher number and many digits allocated for titles; likewise countries publishing much will have few allocated digits for the group identifier, and many for the publishers and titles.^{[17]} Here are some sample ISBN10 codes, illustrating block length variations.
ISBN Country or area Publisher 9992158107 Qatar NCCAH, Doha 9971502100 Singapore World Scientific 9604250590 Greece Sigma Publications 8090273416 Czech Republic; Slovakia Taita Publishers 8535902775 Brazil Companhia das Letras 1843560283 Englishspeaking area Simon Wallenberg Press 0684843285 Englishspeaking area Scribner 080442957X Englishspeaking area Frederick Ungar 0851310419 Englishspeaking area J. A. Allen & Co. 0943396042 Englishspeaking area Willmann–Bell 097522980X Englishspeaking area KT Publishing
Pattern[edit]
Englishlanguage publisher codes follow a systematic pattern, which allows their length to be easily determined, as follows:^{[18]}
Item number length  0 group identifier  1 group identifier  Total  

From  To  Publishers  From  To  Publishers  
6 digits  000xxxxxxx  019xxxxxxx  20  100xxxxxxx  109xxxxxxx  10  30 
5 digits  0200xxxxxx  0699xxxxxx  500  1100xxxxxx  1399xxxxxx  300  800 
4 digits  07000xxxxx  08499xxxxx  1,500  14000xxxxx  15499xxxxx  1,500  3,000 
3 digits  085000xxxx  089999xxxx  5,000  155000xxxx  186979xxxx  31,980  36,980 
2 digits  0900000xxx  0949999xxx  50,000  1869800xxx  1998999xxx  129,200  179,200 
1 digit  09500000xx  09999999xx  500,000  19990000xx  19999999xx  10,000  510,000 
Total  557,020  Total  172,990  730,010 
Check digits[edit]
A check digit is a form of redundancy check used for error detection, the decimal equivalent of a binary checksum. It consists of a single digit computed from the other digits in the message.
ISBN10[edit]
The 2001 edition of the official manual of the International ISBN Agency says that the ISBN10 check digit^{[19]} – which is the last digit of the tendigit ISBN – must range from 0 to 10 (the symbol X is used instead of 10) and must be such that the sum of all the ten digits, each multiplied by the integer weight, descending from 10 to 1, is a multiple of the number 11. Modular arithmetic is convenient for calculating the check digit using modulus 11. Each of the first nine digits of the tendigit ISBN – excluding the check digit, itself – is multiplied by a number in a sequence from 10 to 2, and the remainder of the sum, with respect to 11, is computed. The resulting remainder, plus the check digit, must equal 11; therefore, the check digit is 11 minus the remainder of the sum of the products.
For example, the check digit for an ISBN10 of 030640615? 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) \\ &= 0 + 27 + 0 + 42 + 24 + 0 + 24 + 3 + 10 \\ &= 130 = 11\times 11 + 9
\end{align} </math>
Thus the remainder is 9, the check digit is 2, and the complete sequence is ISBN 0306406152.
Formally, the check digit calculation is:
 <math>(10x_1 + 9x_2 + 8x_3 + 7x_4 + 6x_5 + 5x_6 + 4x_7 + 3x_8 + 2x_9 + x_{10})\mod{11} \equiv 0. </math>
The value <math>x_{10}</math> required to satisfy this condition might be 10; if so, an 'X' should be used.
The two most common errors in handling an ISBN (e.g., typing or writing it) are an altered digit or the transposition of adjacent digits. The ISBN check digit method ensures that these two errors will always be detected. However, if the error occurs in the publishing house and goes undetected, the book will be issued with an invalid ISBN.^{[20]}
Alternative calculation[edit]
The simplest way to verify an ISBN is to compute a sum of the digits of the ISBN:
// C++
bool is_isbn_valid(char digits[10]) {
int i, a = 0, b = 0;
for (i = 0; i < 10; i++) {
a += digits[i]; // Assumed already converted from ASCII to 0..9
b += a;
}
return b % 11 == 0;
}
// Java
public static boolean isISBN10Valid(String isbn) {
int check = 0;
String t = isbn.substring(9);
for (int i = 0; i < 9; i++) {
check += Integer.valueOf(isbn.substring(i, i + 1)) * (10  i);
}
check += (t.equals("x")  t.equals("X")) ? 10 : Integer.valueOf(t);
return check % 11 == 0 ;
}
Template:Show 
The ISBN10 checkdigit can also be calculated in a slightly easier way:
 <math>x_{10} = ( 1x_1 + 2x_2 + 3x_3 + 4x_4 + 5x_5 + 6x_6 + 7x_7 +8x_8 + 9x_9 )\, \bmod\;11. </math>
This is simply replacing 11 with 0, and each subtraction with its complement: <math>10 \equiv 1 \mod 11,</math> etc.
For example, the check digit for an ISBN10 of 030640615? is calculated as follows:
 <math>(1 \times 0 + 2 \times 3 + 3 \times 0 + 4 \times 6 + 5 \times 4 + 6 \times 0 + 7 \times 6 + 8 \times 1 + 9 \times 5) \, \bmod\; 11 = 145 \, \bmod\; 11 = 2</math>
ISBN13[edit]
The 2005 edition of the International ISBN Agency's official manual^{[21]} covering some ISBNs issued from January 2007, describes how the 13digit ISBN check digit is calculated.
The calculation of an ISBN13 check digit begins with the first 12 digits of the thirteendigit 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 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 ISBN13 check digit of 978030640615? is calculated as follows:
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 ISBN 9780306406157.
Formally, the ISBN13 check digit calculation is:
 <math>x_{13} = \big(10  \big(x_1 + 3x_2 + x_3 + 3x_4 + \cdots + x_{11} + 3x_{12}\big) \,\bmod\, 10\big) \,\bmod\, 10. </math>
This check system – similar to the UPC check digit formula – 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 ISBN10 formula uses the prime modulus 11 which avoids this blind spot, but requires more than the digits 09 to express the check digit.
Additionally, If you triple the sum of the 2nd, 4th, 6th, 8th, 10th, and 12th digits and then add them 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).
// Java
public static boolean isISBN13Valid(String isbn) {
int check = 0;
for (int i = 0; i < 12; i += 2) {
check += Integer.valueOf(isbn.substring(i, i + 1));
}
for (int i = 1; i < 12; i += 2) {
check += Integer.valueOf(isbn.substring(i, i + 1)) * 3;
}
check += Integer.valueOf(isbn.substring(12));
return check % 10 == 0;
}
//PHP
function is_isbn_13_valid($n){
$check = 0;
for ($i = 0; $i < 13; $i+=2) $check += substr($n, $i, 1);
for ($i = 1; $i < 12; $i+=2) $check += 3 * substr($n, $i, 1);
return $check % 10 == 0;
}
# Ruby
def is_valid_isbn13?(isbn13)
sum = 0
13.times { i sum += i.modulo(2)==0 ? isbn13[i].to_i : isbn13[i].to_i*3 }
0 == sum.modulo(10)
end
def isbn13_checksum(isbn12)
sum = 0
12.times { i sum += i.modulo(2)==0 ? isbn12[i].to_i : isbn12[i].to_i*3 }
10  sum.modulo(10)
end
# Python
def is_valid_isbn13(isbn13):
total = sum([int(num)*weight for num, weight in zip(isbn13, (1,3)*6)])
ck = 10(total%10)
return ck == int(isbn13[1])
# C/C++
bool is_valid_isbn13(char digits[13])
{
int i, check=0;
for (i=0; i<13; i+=2)
check += digits[i];
for (i=1; i<12; i+=2)
check += 3*digits[i];
return check%10==0;
}
Errors in usage[edit]
Publishers and 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.^{[22]}
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".^{[23]} However, bookordering systems such as Amazon.com will not search for a book if an invalid ISBN is entered to its search engine.
EAN format used in barcodes, and upgrading[edit]
Currently the barcodes on a book's back cover (or inside a massmarket paperback book's front cover) are EAN13; they may have a separate barcode encoding five digits for the currency and the recommended retail price.^{[24]} 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 thirteendigit ISBN (ISBN13). The process began January 1, 2005 and was planned to conclude January 1, 2007.^{[25]} As of 2011, all the 13digit ISBNs begin with 978. As the 978 ISBN supply is exhausted, the 979 prefix will be introduced. This is expected to occur more rapidly outside the United States. Originally, 979 was the Musicland code for musical scores with an ISMN. However, ISMN codes will differ visually as they begin with an "M" letter; the bar code represents the "M" as a zero (0), and for checksum purposes it will count as a 3.
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 tendigit ISBN check digit generally is not the same as the thirteendigit ISBN check digit. Because the EAN/UCC13 is part of the Global Trade Item Number (GTIN) system (that includes the EAN/UCC14, the UPC12, and the EAN8), it is expected that ISBNgenerating software should accommodate fourteendigit ISBNs.^{[26]}
Barcode format compatibility is maintained, because (aside from the group breaks) the ISBN13 barcode format is identical to the EAN barcode format of existing ISBN10s. So, migration to an EANbased system allows booksellers the use of a single numbering system for both books and nonbook products that is compatible with existing ISBNbased data, with only minimal changes to information technology systems. Hence, many booksellers (e.g., Barnes & Noble) migrated to EAN barcodes as early as March 2005. Although many American and Canadian booksellers were able to read EAN13 barcodes before 2005, most general retailers could not read them. The upgrading of the UPC barcode system to full EAN13, in 2005, eased migration to the ISBN13 in North America. Moreover, by January 2007, most large book publishers added ISBN13 barcodes alongside the tendigit ISBN barcodes of books published before January 2007.^{[27]}
See also[edit]
 ASIN (Amazon Standard Identification Number)
 CODEN (serial publication identifier currently used by libraries; replaced by the ISSN for new works)
 DOI (Digital Object Identifier)
 ESTC (English Short Title Catalogue)
 ETTN (Electronic Textbook Track Number)
 ISAN (International Standard Audiovisual Number)
 ISMN (International Standard Music Number)
 ISWC (International Standard Musical Work Code)
 ISRC (International Standard Recording Code)
 ISSN (International Standard Serial Number)
 ISWN (International Standard Wine Number)
 LCCN (Library of Congress Control Number)
 List of group0 ISBN publisher codes
 List of group1 ISBN publisher codes
 OCLC number (Online Computer Library Center number [1])
 Registration authority
 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[edit]
 ↑ 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, 0805000763. Conversely, books are published with several ISBNs: A German, secondlanguage edition of Emil und die Detektive has the ISBNs 8723901578 (Denmark), 0821910698 (United States), 912115628X (Sweden), 0850485487 (England) and 3126754953 (Germany).
 ↑ In some cases, books sold only as sets share ISBNs. For example, the Vance Integral Edition used only 2 ISBNs for 44 books.
 ↑ Gordon Fosters original 1966 report can be found at Informaticsdevelopmentinstitute.net
 ↑ ^{4.0} ^{4.1} .
 ↑ .
 ↑ .
 ↑ Bradley, Philip (1992). "Template:PDFlink. The Indexer. 18 (1): 25–26.
 ↑ Template:PDFlink
 ↑ ^{9.0} ^{9.1} Hailman, Jack Parker (2008). Coding and redundancy: manmade and animalevolved signals. Harvard University Press. P. 209. ISBN 9780674027954.
 ↑ Some books have several codes in the first block: e.g. A. M. Yaglom's Correlation Theory..., published by Springer Verlag, has two ISBNs, 0387963316 and 3540963316. 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 443196331? would also have check digit ? = 6. Other Springer books in English have publisher code 817, and 081796331? 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.
 ↑ ^{11.0} ^{11.1} ^{11.2} Reed, Kennette (2008). From Idea to Author: How to Become Successfully Published. KRA Publications. P. 47. ISBN 9780971371842.
 ↑ The international ISBN agency's ISBN User's Manual says: "The tendigit number is divided into four parts of variable length, which must be separated clearly, by hyphens or spaces" although permitting their omission for internal data processing, as the prefix code ensures that no two codes begin the same way. If present, hyphens must be correctly placed; see hyphenation instructions at ISBN.org.
 ↑ Bowker  ISBN. ThorpeBowker (Jan 5, 2009). Retrieved on March 29, 2012.
 ↑ Friedlander, Joel (May 19, 2010). Bowker's Andy Weissberg on ISBN and the Future. The Book Designer. Retrieved on February 12, 2011.
 ↑ See 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.
 ↑ See Publisher's International ISBN Directory
 ↑ Splane, Lily (2002). The Book Book: A Complete Guide to Creating a Book on Your Computer. Anaphase II Publishing. p. 37. ISBN 9780945962144.
 ↑ Hyphenation Instructions. ISBN.org.
 ↑ Template:PDFlink
 ↑ For example I'saka: a sketch grammar of a language of northcentral New Guinea. Pacific Linguistics. ISBN "0858835544".
 ↑ Template:PDFlink
 ↑ Lorimer, Rowland; Shoichet, Jillian; Maxwell, John W. (2005). Book Publishing I. CCSP Press. p. 299. ISBN 9780973872705.
 ↑ 020  International Standard Book Number (R) – MARC 21 Bibliographic  Full. Library of Congress.
 ↑ EAN13Methodology — including a detailed description of the EAN13 format.
 ↑ There is a FAQ document about this migration.
 ↑ Are You Ready for ISBN13? at isbn.org.
 ↑ Willan, Terry. Template:PDFlink Talis.
External links[edit]
 ISO 2108:2005 at www.iso.org
 ISBN to EAN EAS^{[disambiguation needed]} EBS^{[disambiguation needed]} transition at isbn.org
 Description of the ISBN to EAN upgrade process at bookweb.org
 International ISBN Agency—coordinates and supervises the worldwide use of the ISBN system.
 Numerical List of Group Identifiers List of language/region prefixes
 Free conversion tool: ISBN10 to ISBN13 & ISBN13 to ISBN10 from the ISBN agency. Also shows correct hyphenation & verifies if ISBNs are valid or not.
 RFC 3187 Using International Standard Book Numbers as Uniform Resource Names (URN)
 Template:PDFlink for the 13digit ISBN code.
Template:Audiovisual works Template:ISO standards
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