Não informado. (1919). Foreign crops and markets. U.S. Department of Agriculture, Foreign Agricultural Service.
Chicago-referens (17:e uppl.)Não informado. Foreign Crops and Markets. Washington: U.S. Department of Agriculture, Foreign Agricultural Service, 1919.
MLA-referens (8:e uppl.)Não informado. Foreign Crops and Markets. U.S. Department of Agriculture, Foreign Agricultural Service, 1919.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.