Brecht, Arnold
Political theory: the foundations of twentieth-century political thought
Princenton University Press, 1960
 Buku Teks
Australian conservatism : essays in twentieth century political history
editor, Cameron Hazlehurst
Australian National University Press, 1979
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The Routledge dictionary of twentieth-century political thinkers
edited by Robert Benewick and Philip Green
Routledge , 1992
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Robbins, Lionel
The economist in the twentieth century and the other lectures in political economy
Macmillan, 1954
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Schapiro, J. Salwyn
The world in crisis : political and social movement in the twentieth century / J. Salwyn Schapiro
McGraw-Hill Book Company, Inc., 1950
 Buku Teks