Keylor, William R., 1944-
The twentieth-century world
Oxford University Press, 1996
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Ewen, David
The world of twentieth-century music
Prentice Hall, 1968
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Keylor, William R., 1944-
The twentieth-century world : an international history
Oxford University Press, 1996
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Simai, Mihály
Global power structure, technology and world economy in the late twentieth century
Pinter Publishers , 1990
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Snyder, Louis L.
World in the twentieth century
Princeton University Press, 1964
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