Adrey E. Borell / Chester J. Francis / Irvin Fay Reed / James Vermeer / M. Connor Ahrens / Marie B. Harmon / Marshall Harris / Merrill Sylvester Timmins / Norman Allen / Norman Carroll Teter / United States. Agricultural Research Service. Agricultural Engineering Research Division / W. S. Chepil / Walter Ernest Fleming / Wayland Arthur Shands / William E. Larson / Birely J. Landis / F. M. Grant / Francis Raymond Lawson / Howard Lyle Hill / Irving Rollins Starbird / Neal P. Woodruff / Oliver W. Beale / Paul M. Scheffer / Virgil Lee Hurlburt / F. H. Siddoway / William John Reid | 