Revolutions of the late twentieth century
edited by Jack A. Goldstone, Ted Robert Gurr, Farrokh Moshiri
Westview Press, 1991
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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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Snyder, Louis L.
World in the twentieth century
Princeton University Press, 1964
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Black, C.E.
Twentieth Century Europa: a history
Alfred A. Knopf, 1961
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