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@vocab-term-identifier Points to the Specific Term

The @vocab-term-identifier attribute value points to a unique identifier of the term within a specific vocabulary, such as (but not limited to) an item number, a URI, DOI, etc.

For example, for the term “contributor” for Dublin Core:
http://dublincore.org/usage/terms/history/#contributor-006

<publisher>
    <publisher-name vocab="dcmi"
      vocab-identifier="http://dublincore.org/documents/2012/06/14/dcmi-terms/"
      vocab-term="publisher"
      vocab-term-identifier="http://purl.org/dc/elements/1.1/publisher"
    <publisher-name>British Medical Journal</publisher-name>
  </publisher>
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