USDA Farmers' Bulletin No. 1732 by H.V. Hablan, principal agronomist, and G.A. Wiehe, agronomist, Division of Cereal Crops and Diseases, Bureau of Plant Industry; 1940
USDA Farmers' Bulletin No. 1732 by H.V. Hablan, principal agronomist, and G.A. Wiehe, agronomist, Division of Cereal Crops and Diseases, Bureau of Plant Industry; 1940