Gemmill, P. F. (1948). Economics: Principles and problems (3rd ed. vol. 1 & 2.). Harper.
Dyfyniad Arddull ChicagoGemmill, Paul F. Economics: Principles and Problems. 3rd ed. vol. 1 & 2. New York: Harper, 1948.
Dyfyniad MLAGemmill, Paul F. Economics: Principles and Problems. 3rd ed. vol. 1 & 2. Harper, 1948.
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