Cox, Joseph Frank. Crops : a self-teaching course : based on crop management and soil conservation - New York : Wiley, 1937 - 307 p. : ilus. 2c. ed. x EVA. Romed forces Institute LCCN: 34981 Subjects--Topical Terms: Cultivos--E.U.A.Suelos--Conservación--E.U.A. Dewey Class. No.: 633 / C69c