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Document Type Definitions (DTDs) for NLM Databases

The purpose of a DTD (Document Type Definition) is to define the building blocks of an XML document. It defines the document structure with a list of allowable elements. Below are the DTDs that define NLM XML data.

DTDs for Leased NLM Databases

MEDLINE®/PubMed® DTD:

NLM Catalog DTD:

Other Databases:

See also the Entrez DTDs.

DTDs for Data Supporting Leased NLM Databases

Current (2014) Forthcoming (2015)

List of Serials Indexed for Online Users (LSIOU):

List of Serials Indexed for Online Users (LSIOU):
MeSH® DTDs:

For more information, see the MeSH Download page.

DTDs for Historical Data

HMD DTDs: