Johnson, Stanley R.; Meyers, William H.; Hayes, Dermot J.; Smith, Darnell; Helmar, Michael D.; Oerter, Karen; Premakumar, V.; Westhoff, Patrick; Stephens, Deborah L.; Clemens, Roxanne L.; Doorenbos, Russell; Stephens, Kyle J.; Wharff, Michael D.

Iowa Soybean Promotion Board, Ames: Center for Agriculture and Rural Development, (1993)

abstract currently unavailable