Bulliet, R. W., & Bulliet, R. W. (1998). The Columbia history of the 20th century. New York: Columbia University Press.
Παραπομπή Chicago StyleBulliet, Richard W., and Richard W. Bulliet. The Columbia History of the 20th Century. New York: Columbia University Press, 1998.
Παραπομπή MLABulliet, Richard W., and Richard W. Bulliet. The Columbia History of the 20th Century. New York: Columbia University Press, 1998.
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