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What is ISSN?

ISSN is a worldwide identification code used by publishers, suppliers, libraries, information services, bar coding systems, union catalogues, etc. for citation and retrieval of serials such as Journals, Newspapers, Newsletters, Directories, Yearbooks, Annual Reports & Monograph series, etc. The benefits include international publicity and recognition of the serial by automatic inclusion in the International Serials Directory Database.

It is an eight digit number consisting of seven digits plus a check digit which enables a computer to recognise when the number is incorrectly cited. The check digit may be an X, otherwise the ISSN is fully numeric.