| 1. |  | Illinois-Wisconsin, Pecatonica quadrangle. | Pecatonica (Ill.); Illinois; Wisconsin; Maps; Topographic maps; Topography | 1 map : col.; "Contour interval 10 feet"; "Surveyed in 1915 and 1931-1932"; Shows roadway classification as of 1935.; Coordinates: (W 89⁰30’00"--W 89⁰15’00"/N 42⁰30’00"--N 42⁰15’00") |
