Marcus, Edward
Investment and development possibilities in tropical Africa
Bookman Associates, 1960
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Coughlan, Robert
Tropical Africa
Time Incorporated, 1962
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The demography of tropical Africa
by William Brass ... [et al.]
Princenton University Press, 1968
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The population of tropical Africa
edited by John C. Caldwell and Chukuka Okonjo
Longmans, Green, 1968
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Mackintosh, A.S.
The development of firms an empirical study with special reference to the economic effects of taxation/ A.S. Mackintosh
Cambridge University Press , 1963
 Buku Teks