The third edition succeeds the fifth update of second edition. One of the main features has been the adoption of new and revised international standards, notably the International Standard Identifier for Libraries and Related Organizations, the ISBN 13 and the linking ISSN. New fields have been added for recording the Persistent Record Identifier. Uniform Conventional Headings for Legal and Religious texts are now catered for with separate fields. A number of fields have been revised: archival materials, manuscripts and documentation produced by the ISSN International Centre.