Não informado. (1941). Crop Production. Department of Agriculture, Statistical Reporting Service.
Chicago-Zitierstil (17. Ausg.)Não informado. Crop Production. Washington: Department of Agriculture, Statistical Reporting Service, 1941.
MLA-Zitierstil (8. Ausg.)Não informado. Crop Production. Department of Agriculture, Statistical Reporting Service, 1941.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.