@book{bhlitem55739, title = {Soybeans : their effect on soil productivity }, copyright = {Not provided. Contact Holding Institution to verify copyright status.}, url = {https://www.biodiversitylibrary.org/item/55739}, note = {https://www.biodiversitylibrary.org/bibliography/16709}, publisher = {Urbana, Ill, University of Illinois Agricultural Experiment Station, 1939}, author = {Sears, Ogle Hesse,}, year = {}, pages = {40}, keywords = {Crop rotation|Crops and soils|Soybean|}, }