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TSD / Cataloging and Metadata Management: Fundamentals of the NLM® Classification

Using the Online NLM® Classification

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Hyperlinks on Homepage


Links are provided on the homepage to documentation of structure and content of the NLM Classification, the practices applied, and related resources and databases

Hyperlinks on the Left Side of the Homepage

  • NLM Policy on Classification: Links to the NLM Cataloging Section’s policy document on classification
  • Scope of Revision for the ….. Edition: Provides a synopsis of the additions and changes for the current edition
  • Class Numbers Added and Canceled (Current Edition): Links to list of new class numbers and class numbers made obsolete for the current edition
  • Class Numbers Added (Cumulative List: Links to list of new class numbers added from 2002 (year the NLM Classification was first published in electronic form) through the current year.
  • Canceled Class Numbers (Cumulative List): Links to list of class numbers made obsolete since 1978. Hyperlinks are provided to the current class number for the concept

NLM Classification Materials

  • NLM Classification Poster: Links to instructions for obtaining the 18" x 24" poster which outlines the NLM Classification. A Hyperlink is provided for downloading the 8.5" x 11" PDF version


Last Reviewed: April 16, 2021