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International Standard Book Numbers

Some of our patrons are curious about International Standard Book Numbers, or ISBNs. Allocation of ISBNs is done by the International ISBN Agency in Berlin through international ISBN agencies. The assigned ISBN is printed on the reverse of the title page and on the back of the cover.

ISBNs are composed of 4 parts: a group or country identifier; a publisher identifier; a title identifier; and a check digit.

There is an extended discussion about the process involved in obtaining an ISBN on Bowker’s ISBN Application Process information page. Publishers who already have an ISBN Prefix can use the BowkerLink Publisher Access System to register new titles electronically. Bowker is the ISBN group agency for the United States. Foreign publishers apply for ISBNs directly from the International ISBN Agencies in which their countries participate.

If you are interested in searching for information about books using ISBN numbers, both Amazon.com and the Barnes and Noble.com will allow you to search their extensive list of books available by ISBN, or you can use the Library of Congress catalog to search by ISBN (choose the "Guided Keyword" option, and then select the "International Standard Numbers" index.)