Darton, Nelson Horatio (1920). Syracuse-Lakin folio, Kansas. Folios of the Geologic Atlas, No. 212: United States Department of the Interior, U.S. Geological Survey. p. 17 (plate 2). Archived from the original on 4 October 2011. Retrieved 6 October 2010.{{cite book}}: CS1 maint: location (link)
usgs.gov
tapestry.usgs.gov
"Physiographic Regions". U.S. Department of the Interior. U.S. Geological Survey. Archived from the original on 15 May 2006. Retrieved 2010-10-06.
Darton, Nelson Horatio (1920). Syracuse-Lakin folio, Kansas. Folios of the Geologic Atlas, No. 212: United States Department of the Interior, U.S. Geological Survey. p. 17 (plate 2). Archived from the original on 4 October 2011. Retrieved 6 October 2010.{{cite book}}: CS1 maint: location (link)
"Physiographic Regions". U.S. Department of the Interior. U.S. Geological Survey. Archived from the original on 15 May 2006. Retrieved 2010-10-06.