| 2. |  | Illinois, Ina quadrangle : 15-minute series | Illinois ; Maps ; Topographic maps ; Topography ; Ina (Ill.) | 1 map : col.; Relief shown by contours and spot heights.; "Surveyed in 1921, 1930, and 1937-1939."; "Contour interval 10 feet."; Road classification as of 1942.; Coordinates: (W 89⁰00ʹ00ʺ--W 88⁰45ʹ00ʺ/N... |