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

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Diachronic works (sometimes called continuing resources) are publications in any physical or electronic format intended published over time. They may be successive works, such as serials, which are issued in discrete parts or issues or integrating works where the changes are subsumed in the latest iteration and the content of the previous iterations is no longer accessible.


Serial Publications

  • Almost all serials at NLM are classified in the form number W1, rather than by topic


Last Reviewed: April 16, 2021