AGRICOLA CAT 92263967; Bibliographical supplement to "How farm people accept new ideas." Review of Extension Research 1946/47-1956, Extension Service Circular 506, U.S. Department of Agriculture, Washington, D.C., Ames, Iowa : Agricultural Experiment Station, Iowa State College, 1956. 8 p. (North central regional publication ; no. 1, Sup.; Iowa State College special report no. 15, sup.), References to 87 studies related to the process by which new practices diffuse.