Sources examined in the compilation of this list are the card catalogues of the U. S. Department of Agriculture Library and the Bureau, of Agricultural Economics Library; the Botanical Catalogue of the Bureau of Plant Industry Library; Agricultural Economics Literature, 1928-1940; Agricultural Index, 1919-Sept. 1940; Experiment Station Record, 1912-1940; Public Affairs Information Service Bulletin, 1930-Mar. 1941; Industrial Arts Index, 1913-1940.; Readers' Guide to Periodical Literature, 1910-Eeb. 25, 1941; International Index to Periodicals, 1920-Jan. 1941. Call numbers following the citations are these of the U. S. Department of Agriculture Library.