| 3. |  | Illinois-Missouri, Nebo quadrangle. | Nebo (Ill.); Missouri; Illinois; Maps; Topographic maps; Topography | 1 map : col.; 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 1926-1927."; "Contour interval 20... |