Martin, J. H., & Leonard, W. H. (1949). Principles of field crop production. Macmillan.
Chicago Style (17th ed.) CitationMartin, John H., and Warren H. Leonard. Principles of Field Crop Production. New York: Macmillan, 1949.
MLA (9th ed.) CitationMartin, John H., and Warren H. Leonard. Principles of Field Crop Production. Macmillan, 1949.