University of Illinois Agricultural Experiment Station Bulletin No. 94: Nitrogen Bacteria and LegumesWith special reference to red clover, cowpeas, soy beans,alfalfa, and sweet clover, on Illinois soils

University of Illinois Agricultural Experiment Station Bulletin No. 94: Nitrogen Bacteria and LegumesWith special reference to red clover, cowpeas, soy beans,alfalfa, and sweet clover, on Illinois soilsCyril G. (Cyril George) Hopkins · Rights: US