Schapiro, J. Salwyn
The world in crisis : political and social movement in the twentieth century / J. Salwyn Schapiro
McGraw-Hill Book Company, Inc., 1950
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Button, John
The radicalism handbook : a complete guide to the radical movement in the twentieth century
Cassell, 1995
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Margolies, Edward
Native sons : a critical study of twentieth-century Negro American authors / Edward Margolies
Lippincott, 1969
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Revolutions of the late twentieth century
edited by Jack A. Goldstone, Ted Robert Gurr, Farrokh Moshiri
Westview Press, 1991
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Varga, Eugen, 1879-1964
Twentieth century capitalism
Foreign Languages Publishing House, 1961
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