by Lindgren, H.E. (North Dakota State University, Fargo, ND)
Published in North Dakota farm research (01.07.1990)

by Rogers, D.A., Cater, A., Clambey, G.K., Garrison, M., Hanson, R.A., Harrold, R.L., Henderson, W.M., Keogh, A.J., Lindgren, H.E.
Published in Proceedings of IEEE Frontiers in Education Conference - FIE '93 (1993)