Over, W. H. (1923). Trees and shrubs of South Dakota. Pub. by the University.
Chicago-referens (17:e uppl.)Over, William H. Trees and Shrubs of South Dakota. Vermillion, S.D.: Pub. by the University, 1923.
MLA-referens (8:e uppl.)Over, William H. Trees and Shrubs of South Dakota. Pub. by the University, 1923.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.