Columbia subject headings:
Harvard subject headings:
Byzantine Empire--History--Sources.
Egypt--History--640-1250--Sources.
Princeton subject headings:
Byzantine Empire--History--527-1081--Early works to 1800.
Egypt--Church history--Early works to 1800.
Egypt--History--30 B.C.-640 A.D.--Early works to 1800.
Egypt--History--640-1250--Early works to 1800.
History, Ancient--Early works to 1800.