American Society of Agricultural Engineers Conference on Crop Production with Conservation in the 80's Chicago, Ill., & American Society of Agricultural Engineers. (1981). Crop production with conservation in the 80's: Proceedings of the American Society of Agricultural Engineers Conference on Crop Production with Conservation in the 80's, December 1-2, 1980, Palmer House, Chicago, Illinois. ASAE.

American Society of Agricultural Engineers Conference on Crop Production with Conservation in the 80's Chicago, Ill., and American Society of Agricultural Engineers. Crop Production with Conservation in the 80's: Proceedings of the American Society of Agricultural Engineers Conference on Crop Production with Conservation in the 80's, December 1-2, 1980, Palmer House, Chicago, Illinois. St. Joseph, Mich.: ASAE, 1981.

American Society of Agricultural Engineers Conference on Crop Production with Conservation in the 80's Chicago, Ill., and American Society of Agricultural Engineers. Crop Production with Conservation in the 80's: Proceedings of the American Society of Agricultural Engineers Conference on Crop Production with Conservation in the 80's, December 1-2, 1980, Palmer House, Chicago, Illinois. ASAE, 1981.