Agricultural Communications Documentation Center, Funk Library, University of Illinois Document Number: C19155
Notes:
Pages 111-170 in U.S. Department of Agriculture, "Farmers in a changing world," 1940 Yearbook of Agriculture, U.S.Government Printing Office, Washington, D.C. 1,215 pages.
Agricultural Communications Documentation Center, Funk Library, University of Illinois Document Number: C16957
Notes:
Pages 61-69 in Hans-Dieter Klingemann and Andrea Rommele (eds.), Public information campaigns and opinion research: a handbook for the student and practitioner. Sage Publications, London. 193 pages.