Dvornik, F. (1974). Origins of intelligence services: The ancient Near East, Persia, Greece, Rome, Byzantian, the Arab muslim empires, the Mongol empire, China, Muscovy. Rutgers University Press.
Chicago-referens (17:e uppl.)Dvornik, Francis. Origins of Intelligence Services: The Ancient Near East, Persia, Greece, Rome, Byzantian, the Arab Muslim Empires, the Mongol Empire, China, Muscovy. New Brunswick, N. J: Rutgers University Press, 1974.
MLA-referens (9:e uppl.)Dvornik, Francis. Origins of Intelligence Services: The Ancient Near East, Persia, Greece, Rome, Byzantian, the Arab Muslim Empires, the Mongol Empire, China, Muscovy. Rutgers University Press, 1974.
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