Epstein, T. Scarlett
Capitalism, primitive and modern : some aspects of Tolai economic growth
Australian National University Press, 1968
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Hegeland, Hugo
The quantity theory of money a critical study of its historical development and interpretation and a restatement
Elanders Boktryckeri Aktiebolag, 1951
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Quiggin, A. Hingston
A survey of primitive money : the beginning of currency
Methuen, 1949
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Nash, Manning
Primitive and peasant economic systems
Chandler Publishing Company, 1966
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Twyford, H.B.
Purchasing its economic aspects and proper methods / H.B. Twyford
Van Nostrand Co., 1915
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