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

General Principles

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Editions

  • In general, NLM assigns the same classification to new editions of a work as that of the immediately preceding edition unless:
  • NLM does not revise the classification of an earlier edition if it was correctly classified according to the schedule in use at that time. Egregious errors are corrected

Translations

  • In general, NLM classifies a translation with the original work, unless a more appropriate number has been added to the classification schedule
  • NLM does not reclassify the original publication if it was correctly classified according to the schedule in use at the time

Reprints/Facsimiles

  • NLM always classifies reprints and facsimiles using the original class number
  • Consider a modern compilation of reprints of pre-20th century articles or works to be a modern work.  Classify collections of reprinted papers in the appropriate number for the subject
  • Reprints of several works that include publications from the 20th century or later are classed with current works

Supplements

  • For separately published works that are dependent on another work to be fully useable (e.g., review manuals, study guides, updates, etc.), assign the same classification and cutter number as for the main work
  • Append the word “Suppl.” and the year of publication of the supplement to the call number for the main work
  • These instructions apply even if a publication type is assigned to the supplement that would normally require classification by form number.  In such cases, do not classify by the form number; use the classification number of the main work
  • Example:
    • Parent volume, published in 2008
      • 060 00  $a WB 105  $b E537 2008
    • Supplement published in 2009
      • 060 00  $a WB 105  $b E537 2008 Suppl. 2009

Companion Volumes

  • For independent works that are identified as "companion volumes" or "sequels" to another work, classify for the actual content, not necessarily paralleling the classification of the original work


Last Reviewed: April 16, 2021