by Boyd, J. (University of Arkansas.)
Published in FSA (USA) (01.11.1994)

by Boyd, J. (University of Arkansas)
Published in FSA - Cooperative Extension Service, University of Arkansas (USA) (01.08.1992)

by Boyd, J. (University of Arkansas.)
Published in FSA (USA) (01.12.1991)

by Boyd, J. (Cooperative Extension Service, University of Arkansas)
Published in Fact sheet - University of Arkansas, Cooperative Extension Service (USA) (01.06.1989)