<P> 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 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 ISO on - line facility only refers back to 1978 . </P> <P> 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 "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 . </P> <P> Since 1 January 2007, ISBNs have contained 13 digits, a format that is compatible with "Bookland" European Article Number EAN - 13s . </P> <P> 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 . 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): </P>

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