by University of Vermont

1930

by Vermont. University. Agricultural Experiment Station

1914

by University of Vermont. Agricultural Extension Service

1915

by University of Vermont

1902

by University of Vermont. Extension Service

1916

by University of Tennessee (Knoxville campus). Department of Agricultural Education

1921

by University of Vermont. Extension Service

1929

by University of Massachusetts (Amherst campus). Cooperative Extension Service

1928