1. Peterson , C.L. G.L. Wagner D.L. Auld 1981 Winter Meeting of ASAE, Chicago, IL
2. Hofman , V. K. Kaufman D. Helgeson W.E. Dinusson Sunflower for Power, NDSU Cooperative Extension Service Circular AE-735, Fargo, ND 1981
3. Quick , G.R. ASAE Technical Paper No. 801525, ASAE, St. Joseph, MI 1980
4. Goering , C.E. J.J. Daugherty 1981 Winter Meeting of ASAE, Chicago
5. Bettis , B.L. Master's Thesis, University of Idaho, Moscow 1982