by University of Missouri--Columbia. Agricultural Experiment Station

1921

by University of Tennessee, Knoxville. Agricultural Experiment Station

1927

by University of Kentucky

1917

by Kentucky. University, University of Kentucky

1920

by University of Kentucky

1917

by University of Hawaii (Honolulu). Agricultural Extension Service

1929

by Rutgers University. Cooperative Extension Service

1923

by Ohio State University. Agricultural Extension Service

1919

by Kentucky. University, University of Kentucky

1919

by University of Nebraska (Lincoln campus). Conservation and Survey Division

1928

by West Virginia University. Cooperative Extension Service

1918

by University of Illinois (Urbana-Champaign campus)

1923