Não informado. (1971). American bibliography of agricultural economics. University of Kentucky, Department of Agricultural Economics, American Agricultural Economics.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. American Bibliography of Agricultural Economics. Lexington, Ky: University of Kentucky, Department of Agricultural Economics, American Agricultural Economics, 1971.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. American Bibliography of Agricultural Economics. University of Kentucky, Department of Agricultural Economics, American Agricultural Economics, 1971.
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