by United States. Bureau of Agricultural Economics

1923

by United States. Bureau of Agricultural Economics

1928

by United States. Bureau of Agricultural Economics. Library

1937

by United States. Congress. Senate. Select committee on investigation of the Tariff commission

1926

by United States. Office of Education

1917

by United States. Bureau of Agricultural Economics

1941

by United States. Bureau of Agricultural Economics

1925

by United States. Congress. House. Committee on Ways and Means

1929

by United States. Congress. Senate. Committee on Appropriations

1924

by United States. Office of Experiment Stations

1927

by United States. Bureau of Efficiency

1925

by United States. Department of Agriculture

1927