Mitchell, B., & Mitchell, J. E. (1972). The watershed as a resource management unit: A selected bibliography. Council of Planning Librarians.
Chicago-referens (17:e uppl.)Mitchell, Bruce, och Joan Elizabeth Mitchell. The Watershed as a Resource Management Unit: A Selected Bibliography. Monticello, Ill: Council of Planning Librarians, 1972.
MLA-referens (9:e uppl.)Mitchell, Bruce, och Joan Elizabeth Mitchell. The Watershed as a Resource Management Unit: A Selected Bibliography. Council of Planning Librarians, 1972.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.