Primary Sources
USDA Engineering Division Personnel Photographs. 1912-1940. Photograph album of Engineering Division personnel, group and individual shots. The photographs were taken in March 1924.
USDA Division of Agricultural Engineering Records. 1913-1981. The records consist of photographs, glass negatives, acetate negatives, and publications relating to agricultural engineering. Additionally, there are speeches and papers by A. W. Turner who was assistant chief for the Bureau of Plant Industry, Soils, and Agricultural Engineering beginning in 1943, and materials collected for a book to be written on the history of farm electrification by M. Conner Ahrens, former assistant chief, Farm Electrification Research Branch of USDA.