Não informado. (1989). AgExporter. U.S. Department of Agriculture, Foreign Agricultural Service.
Chicago-referens (17:e uppl.)Não informado. AgExporter. Washington: U.S. Department of Agriculture, Foreign Agricultural Service, 1989.
MLA-referens (8:e uppl.)Não informado. AgExporter. U.S. Department of Agriculture, Foreign Agricultural Service, 1989.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.