@misc{indiciae8cd57600572b, title = {Map of land modified by man in part of the Canonsburg 7 1/2-minute Quadrangle, Allegheny County and vicinity, Pennsylvania}, author = {W.E. Davies}, year = {1974}, doi = {10.3133/ofr74287}, url = {https://pubs.usgs.gov/publication/ofr74287}, note = {Source identifier: ofr74287} }