- Geological Survey (U.S.)
- University of Illinois at Urbana-Champaign, University Library
Relief shown by contours and spot heights.; "Culture and drainage in part compiled from aerial photographs taken by Air Corps, U.S. Army"; "Surveyed in 1927-1929 and 1931"; "Contour intervals 5 and 20 feet."; Shows roadway classification as of 1933. 45 x 36 cm.; 1 map, colored. 1:62,500. Geological Survey (U.S.); War Dept., Corps of Engineers, U.S. Army (U.S.); Geological Survey Division (Urbana, Ill.).