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

Using the Online NLM® Classification

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Class Number Format


  • Spaces—Unlike LCC, there is a space between the letter(s) and the number(s). Exception: Even though W1–W9 are displayed online with a space in between, do not input a space when recording these numbers in a bibliographic record.

    Examples:
    QS 16 not QS16
    but
    W2 not W 2

  • Decimals—May or may not indicate subordinate class numbers

    Example of subordinate decimal class number

    Screen capture of the Class Number Format Decimal Subordinate example

    Example of decimal class number that is not subordinate

    Screen capture of the Class Number Format Decimal Not Subordinate example

  • Indentation—Indented schedule captions always indicate class numbers for subordinate concepts

    Example: Class numbers WB 146 through WB 182 are subordinate to WB 143

    Screen capture the Class Number Format Indentation example



Last Reviewed: April 16, 2021