Com & edited by Langer, W. L. (1972). An encyclopedia of world history: Ancient, medieval, and modern Chrnologically arranged. Houghton Mifflin.
Chicago-viite (17. p.)Com & edited by Langer, William L. An Encyclopedia of World History: Ancient, Medieval, and Modern Chrnologically Arranged. Boston: Houghton Mifflin, 1972.
MLA-viite (9. p.)Com & edited by Langer, William L. An Encyclopedia of World History: Ancient, Medieval, and Modern Chrnologically Arranged. Houghton Mifflin, 1972.
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