Physiographic regions of the United States
The physiographic regions of the contiguous United States comprise 8 regions, 25 provinces, and 85 sections. The system dates to Nevin Fenneman's paper Physiographic Subdivision of the United States, published in 1917. Fenneman expanded and presented his system more fully in two books, Physiography of western United States (1931), and Physiography of eastern United States (1938). In these works Fenneman described 25 provinces and 85 sections of the United States physiography.
- "Physiographic Regions". United States Geological Survey. 2003-04-17. Archived from the original on 2006-05-15. Retrieved 2008-01-30.
- Fenneman, Nevin M. (January 1917). "Physiographic Subdivision of the United States". Proceedings of the National Academy of Sciences of the United States of America. 3 (1): 17–22. doi:10.1073/pnas.3.1.17. OCLC 43473694. PMC 1091163. PMID 16586678.
- Fenneman, Nevin Melancthon (1931). Physiography of western United States. McGraw-Hill. OCLC 487636.
- Fenneman, Nevin Melancthon (1938). Physiography of eastern United States. McGraw-Hill. OCLC 487628.
- "Automated IFSAR Terrain Analysis System". Defense Advanced Research Projects Agency (DOD), Information Sciences Office. 31 August 2001. Retrieved 5 October 2010.