ONIX and MARC21
Although ONIX for Books is a trade product information format, the availability of rich metadata from publishers and others has generated considerable interest in the library community. Data from ONIX sources can be used to enhance the content and presentation of library online catalogues, as well as supporting selection and acquisitions. Library representatives play an active part in a number of ONIX national groups.
Several organisations have developed mappings from ONIX to MARC21, the most widely-used format for data exchange among libraries. The most comprehensive recent work in this area has been undertaken by OCLC, and we are very happy to make available through the EDItEUR website two papers by Carol Jean Godby of OCLC’s research staff describing the work and its implications, together with detailed mapping tables in Excel spreadsheet form.
The OCLC work – which covers both ONIX 2.1 and ONIX 3.0 – is set in the context of a Metadata Services programme under which publishers’ ONIX files are used to enrich MARC records in the OCLC database with added content, and at the same time MARC elements can be fed back to enhance the usefulness of the publisher’s metadata feed.
The OCLC Research papers highlight some of the key differences between the two standards. They describe how the OCLC mappings are constructed; indicate areas where conversion is straightforward and others where the process is more problematic; and act as an introduction to the mapping tables. The 2.1 paper also looks to the future, and suggests topics that might be explored in order to make it easier for metadata to be shared between the trade and library communities. The 3.0 paper considers how the mapping might be improved as libraries migrate from using AACR2 to RDA cataloguing rules.
Each paper is accompanied by a ‘crosswalk’ showing in detail how each data element from ONIX is mapped. The crosswalk is an Excel workbook with multiple tables. The first table in either workbook is the master sheet which details all the elements of ONIX for Books and shows how they translate into MARC21. The remaining tables, referenced from the master sheet, provide a further level of detail for specific elements and codelists.
- MARC crosswalk from ONIX 2.1 with Codelists Issue 10
- MARC crosswalk from ONIX 3.0 with Codelists Issue 12
The Library of Congress also publishes an ONIX-to-MARC21 mapping, based on ONIX Release 2.1, on its website. The Library has for some time been piloting the use of ONIX feeds of advance information from publishers as part of its Cataloging-in-Publication (CIP) programme.