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

Components of the NLM® Call Numbers

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Basic Components


  • An NLM call number consists of the following basic components when applicable
    • Classification number
    • Table G number (geographic notation)
    • Cutter number
    • Workmark
    • Volume or issue number
    • Year of publication
    • Supplement number
    • Year of supplement


Last Reviewed: April 16, 2021