Pettyjohn, W. A. (1967). Geological Survey Geohydrology of the Souris River valley in the vicinity of Monot, North Dakota. Washington: United States Government Printing Office.
Chicago-Zitierstil (17. Ausg.)Pettyjohn, Wayne A. Geological Survey Geohydrology of the Souris River Valley in the Vicinity of Monot, North Dakota. Washington: United States Government Printing Office, 1967.
MLA-Zitierstil (9. Ausg.)Pettyjohn, Wayne A. Geological Survey Geohydrology of the Souris River Valley in the Vicinity of Monot, North Dakota. Washington: United States Government Printing Office, 1967.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.