London, Kurt
D.van Nostrand Company,Inc., 1950
Buku Teks
Divine, Robert A., author
New Viewpoints, 1974
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McCamy, James L., author
Alfred A. Knopf, 1952
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Bisson, T.A., author
Macmilan Co., 1945
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Wittkopf, Eugene R., author
Thomson, 2002
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