Spykman, N. J. (1942). America's strategy in world politics, the United States and the balance of power. Harcourt, Brace and Company.
Chicago-viite (17. p.)Spykman, Nicholas John. America's Strategy in World Politics, the United States and the Balance of Power. New York: Harcourt, Brace and Company, 1942.
MLA-viite (9. p.)Spykman, Nicholas John. America's Strategy in World Politics, the United States and the Balance of Power. Harcourt, Brace and Company, 1942.
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