Page 8 in Extension Circular 534, Review of Extension Research, January through December 1960, U.S. Department of Agriculture, Washington, D.C. Summary of Research Bulletin 850, Ohio Agricultural Experiment Station, Ohio State University,Columbus. 1960. 38 pages.
Pages 79-80 in Extension Circular 532, Review of Extension Research, January through December 1959, U.S. Department of Agriculture, Washington, D.C. Summary of research report, master of science in agricultural education, University of Minneapolis, St. Paul. 1959
