Não informado. (1931). Cotton situation. U.S. Department of Agriculture, Bureau of Agricultural Economics.
Citação do estilo Chicago (17ª ed.)Não informado. Cotton Situation. Washington: U.S. Department of Agriculture, Bureau of Agricultural Economics, 1931.
Citação MLA (8ª ed.)Não informado. Cotton Situation. U.S. Department of Agriculture, Bureau of Agricultural Economics, 1931.
警告：這些引文格式不一定是100％准確.