Não informado. (1939). Feed situation. U.S. Department of Agriculture, Bureau of Agricultural Economics.
Chicago-viite (17. p.)Não informado. Feed Situation. Washington: U.S. Department of Agriculture, Bureau of Agricultural Economics, 1939.
MLA-viite (8. p.)Não informado. Feed Situation. U.S. Department of Agriculture, Bureau of Agricultural Economics, 1939.
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