Oxford Dictionary of Byzantium

With more than 5,000 entries by an international group of eminent historians, this is the standard research tool on 1,100 years of Byzantine history. Exhaustive in its coverage, entries on patriarchy and emperors coexist with entries on surgery, musical instruments, and the baking of bread, bringing to life this vastly important culture and empire, from the 4th century to the 15th.

http://www.lib.umn.edu/get/4649

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