Não informado. Report of the Botanist. U.S. Department of Agriculture.
Chicago-referens (17:e uppl.)Não informado. Report of the Botanist. Washington: U.S. Department of Agriculture.
MLA-referens (8:e uppl.)Não informado. Report of the Botanist. U.S. Department of Agriculture.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.