APA Edition Citation

Leonard, W. H., & Martin, J. H. (1949). Principles of field crop production. Macmillan Co.

Chicago Edition Citation

Leonard, Warren H., and John H. Martin. Principles of Field Crop Production. Newyork: Macmillan Co, 1949.

MLA Edition Citation

Leonard, Warren H., and John H. Martin. Principles of Field Crop Production. Macmillan Co, 1949.