Allen, J. M. (1997). Study guide for Ralph, Lerner, Meacham, Wood, Hull, and Burns "World civilizations" (9th ed.). New York ; London: W. W. Norton.
Παραπομπή Chicago StyleAllen, J. Michael. Study Guide for Ralph, Lerner, Meacham, Wood, Hull, and Burns "World Civilizations". 9th ed. New York ; London: W. W. Norton, 1997.
Παραπομπή MLAAllen, J. Michael. Study Guide for Ralph, Lerner, Meacham, Wood, Hull, and Burns "World Civilizations". 9th ed. New York ; London: W. W. Norton, 1997.
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