Source:Dougal
From Pittsburgh Streets
David Dougal and Jno. E. Whiteside. The Map of Allegheny County. 1817. https://www.phmc.state.pa.us/bah/dam/rg/di/r17-534WhitesideMaps/r017_0534_0000_3343_AlleghenyCounty.pdf. Linked from https://sites.psu.edu/mapsgislib/pennsylvania-early-county-maps-and-altases/.
