Academic databases and search engines

This page contains a representative list of major databases and search engines useful in an academic setting for finding and accessing articles in academic journals, repositories, archives, or other collections of scientific and other articles. As the distinction between a database and a search engine is unclear for these complex document retrieval systems, see:

Note that "free" or "subscription" can refer both to the availability of the database or of the journal articles included. This has been indicated as precisely as possible in the lists below.

Material includes unique grey literature such as unpublished scientific and technical reports, theses, conference papers, government publications, and more.

searches among physician level standard documents eliminating patient level materials.

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