by R. Earl Storie ... [and others] ; United States Department of Agriculture, Bureau of Plant Industry, Soils, and Agricultural Engineering in cooperation with the University of California Agricultural Experiment Station
by Ralph C. Cole ... [and others] ; United States Department of Agriculture, Bureau of Plant Industry, Soils, and Agricultural Engineering and Soil Conservation Service in cooperation with the University of California Agricultural Experiment Station
by John L. Retzer ... [and others] ; United States Department of Agriculture, Agricultural Research Administration, Bureau of Plant Industry, Soils and Agricultural Engineering in cooperation with the University of California Agricultural Experiment Station
by Ralph C. Cole ... [and others] ; United States Department of Agriculture, Agricultural Research Administration, Bureau of Plant Industry, Soils, and Agricultural Engineering in cooperation with the University of California Agricultural Experiment Station