Rickard, J.A.
Ancient, medieval and modern history J.A. Rickard and Albert Hyma
New York, N.Y. Barner & Noble, Inc. 1956,
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An encyclopedia of world history : ancient, medieval, and modern chronologically arranged
compiled and edited by William L. Langer
Houghton Mifflin, 1968
 Buku Referensi
Mayer, Frederick
A History of Ancient of Medieval Philosophy / Frederick Mayer.
American Book Company, 1950
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Webster, Hutton
History of Civilization: ancient and medieval; Vol. 2
D.C. Heath, 1947
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Hoffman, Ross J.S.
Medieval history
Littlefield, Adams, 1958
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