George H. Vansell
ARS Pollination Research Workshop (1991 Denver, Colo.)
A. J. Solomon Raju
Hidetomo Oda
Mont A. Cazier
Helen Kennedy
Keith S. Delaplane
Francesca Grazzini
International Symposium on Pollination (7th 1996 Lethbridge, Alta.)
Aileen Lucia Fisher
Jacques Lhonoré
Alice Lightner Hopf
Sylvia A. Johnson
D. F. Mayer
Abishkar Subedi
Norbert de Buck
Charles Darwin
United States. Soil Conservation Service. Upper Mississippi Region
Unknown Author