Não informado. (1931). Cotton situation. U.S. Department of Agriculture, Bureau of Agricultural Economics.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Cotton Situation. Washington: U.S. Department of Agriculture, Bureau of Agricultural Economics, 1931.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Cotton Situation. U.S. Department of Agriculture, Bureau of Agricultural Economics, 1931.
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