TY - RPRT TI - Map of land modified by man in part of the Freeport 7 1/2-minute Quadrangle, Allegheny County and vicinity, Pennsylvania AU - W.E. Davies PY - 1974 DO - 10.3133/ofr74290 UR - https://pubs.usgs.gov/publication/ofr74290 ID - ofr74290 ER -