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MARC 21 Format for Classification Data: Including Guidelines for Content Designation
Network Development and MARC Standards Office, Library of Congress
2000 edition with Updates 1-4 interfiled
Publication Date:
Free download
Discontinued print product. MARC 21 formats and their updates are available free on the Library of Congress MARC web site.

Format specifications for the communication of MARC classification records, which may be used in online public catalog retrieval systems, in systems to maintain and develop classification schedules, and in online systems for library classifiers. Defines the codes and conventions (tags, indicators, subfield codes, and coded values) that identify the data elements in the records.

Developed with a focus on two major classification schemes: Library of Congress Classification and Dewey Decimal Classification, but also supports other classification schemes. Includes a glossary of classification terms and full record examples of LC Classification, Dewey Decimal Classification, National Library of Medicine Classification, and Universal Decimal Classification schemes.
Included in Cataloger's Desktop

Updates also available separately.
Related links:
Concise format
MARC Web Site

Introduction to MARC Documentation

Machine-Readable Cataloging (MARC) is the standard in library automation, forming the backbone of today's automated library systems, networks, and bibliographical utilities. The Library of Congress MARC products set the standard for MARC cataloging documentation. Available in Cataloger's Desktop and free online on the Library's MARC web site,

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