^Wisconsin State Capitol. National Historic Landmark summary listing. National Park Service. [2008-06-30]. (原始内容存档于2009-04-03).
參考資料
Dennis, James M. Karl Bitter Architectural Sculptor: 1867 - 1915. University of Wisconsin Press. 1967年.
Kvaran, Einar Einarsson. Architectural Sculpture in America. unpublished manuscript.
Landau, Sarah Bradford. George B. Post: Picturesque Designer and Determined Realist. New York: The Montacelli Press. 1998年.
Lombardo, Josef Vincent. Atilio Piccirilli: Life of an American Sculptor. New York: Pitman Publishing Corporation. 1944年.
Rajer, Anton and Christine Style. Public Sculpture in Wisconsin: An Atlas of Outdoor Monuments, Memorials and Masterpieces in the Badger State. Madison Wisconsin: SOS! Save Outdoor Sculpture, Wisconsin. 1999年.
Schevill, Ferdinand. Karl Bitter – A Biography. Chicago: University of Chicago Press. 1917年.
Wisconsin State Capitol: Guide and History. Division of Buildings and Grounds, Department of Administration, State of Wisconsin. 1991年.