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• The green links are going toward external applications
• G triggers a Google search
  P triggers a search using PubMed/Entrez.
  M links to PubMed/Entrez and requests a search using MeSH Thesaurus.
• + do the same thing but restricted to MeSH Major Topics*
  The blue links trigger "horizontal searches": clicking an author names searches every document in the repository for the same author. Idem for subjects and ISSNs.
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Indexing :

Within a given application O, Item A.field F may contain one or more "wiki like" links:

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