United States Department of Agriculture, Soil Conservation Service in cooperation with Oklahoma Agricultural Experiment Station ; [by Earl C. Nance ... [and others] ; Correlation by E.H. Templin]
United States Department of Agriculture, Soil Conservation Service in cooperation with Oklahoma Agricultural Experiment Station ; [by Ralph S. Murphy ... and others ; Correlation by E.H. Templin]
United States Department of Agriculture, Soil Conservation Service in cooperation with Oklahoma Agricultural Experiment Station ; [by Harvey Oakes ... and others ; correlation by James Thorp]