Ramos, Fidel V.
The Friends of Steady Eddie , 1996
Buku Teks
Heilbroner, Robert L., author
Harper & Row , 1963
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Christenson, Reo M.
Harper & Row Publishers, 1982
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Burgmann, Verity
Allen & Uwin, 1985
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Bronowski, J.
Little, Brown & Co., 1973
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