United States. Bureau of Agricultural Economics. (1920). Handbook, official grain standards for wheat, shelled corn and oats; tabulated and abridged description of official grain standards of U.S. for wheat and for shelled corn as established and promulgated by Secretary of Agriculture, Apr. 13, 1918, effective July 15, 1918; and for oats as established and promulgated Mar. 15, 1919, effective June 16, 1919. GPO.
Chicago Style (17th ed.) CitationUnited States. Bureau of Agricultural Economics. Handbook, Official Grain Standards for Wheat, Shelled Corn and Oats; Tabulated and Abridged Description of Official Grain Standards of U.S. for Wheat and for Shelled Corn as Established and Promulgated by Secretary of Agriculture, Apr. 13, 1918, Effective July 15, 1918; and for Oats as Established and Promulgated Mar. 15, 1919, Effective June 16, 1919. [Washington]: GPO, 1920.
MLA (9th ed.) CitationUnited States. Bureau of Agricultural Economics. Handbook, Official Grain Standards for Wheat, Shelled Corn and Oats; Tabulated and Abridged Description of Official Grain Standards of U.S. for Wheat and for Shelled Corn as Established and Promulgated by Secretary of Agriculture, Apr. 13, 1918, Effective July 15, 1918; and for Oats as Established and Promulgated Mar. 15, 1919, Effective June 16, 1919. GPO, 1920.