- Geological Survey (U.S.)
- University of Illinois at Urbana-Champaign, University Library
Relief shown by contours and spot heights.; "Surveyed in 1931-1932"; "Contour interval 10 feet"; Shows roadway classification as of 1934.; (W 88⁰00ʹ00ʺ--W 87⁰45ʹ00ʺ/N 40⁰30ʹ00ʺ--N 40⁰15ʹ00ʺ). 45 x 35 cm.; 1 map, colored. 1:62,500. Geological Survey (U.S.); Geological Survey Division (Urbana, Ill).