| 1. |  | Illinois, Mount Olive quadrangle : topography. | Mount Olive (Ill.); Illinois; Maps; Topographic maps; Topography | 1 map : col.; Relief indicated by contours and spot heights.; "Surveyed in 1913"; "Surveyed in cooperation with the State of Illinois."; "Contour interval 20 feet."; Coordinates: (W 89⁰45ʹ00ʺ--W 89⁰30ʹ00ʺ/N... |
