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The most authoritative and extensive encyclopedia for Art is Grove Art Online (available through Oxford Art Online) .
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Oxford Bibliographies are research guides in a variety of subject areas. Combining features of an annotated bibliography and a high-level encyclopedia, this resource directs researchers to top scholarship across a wide variety of topics.
Macmillan Encyclopedia of Architects
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Passion Iconography in Northern European Art of the Late Middle Ages and Early Renaissance
Lexicon Iconographicum Mythologiae Classicae (LIMC)
Medieval Iconography : A Research Guide
Research Guide to the History of Western Art
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