1. Bockheim JG, Hartemink AE. The soils of Wisconsin. Dordrecht: Springer; 2017.
2. Apps J. Wisconsin agriculture—a history. Madison: Wisconsin Historical Society Press; 2015.
3. Anon. 100 Years Independence 1876–1976. Historical album. Independence: City of Independence; 1976.
4. Campbell HC. Wisconsin in three centuries, 1684–1905. New York: Century History Company; 1906.
5. Hole FD. Soils of Wisconsin. Madison: The University of Wisconsin Press; 1976.