Não informado. (1976). Illinois Natural History Survey Special Publications. Department of Energy and Natural Resources, Natural History Division.
Chicago-Zitierstil (17. Ausg.)Não informado. Illinois Natural History Survey Special Publications. Champaign, Ill: Department of Energy and Natural Resources, Natural History Division, 1976.
MLA-Zitierstil (8. Ausg.)Não informado. Illinois Natural History Survey Special Publications. Department of Energy and Natural Resources, Natural History Division, 1976.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.