Cite
[Creator not found], (n.d.). USGS Quadrangle Boundaries and Corner Points [Illinois]. Illinois Geospatial Data Clearinghouse. https://clearinghouse.isgs.illinois.edu/data/reference/usgs-quadrangle-boundaries-and-corner-points-illinois (dataset)
Available from: https://geo.btaa.org/catalog/02a-01_reference-usgs-quadrangle-boundaries-and-corner-points-illinois