A subject-specific encyclopedia (or encyclopedic set) is a single (or multi-volume) reference work that provides background information on a more specialized discipline.

Full-text articles from multi-volume encyclopedias, biographical collections, business plan handbooks, company history compilations, consumer health references, and specialized reference sources.
Concise Encyclopedia of Semiconducting Materials & Related Technologies
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Encyclopedia of RF and Microwave Engineering
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The Optics Encyclopedia
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