TY  - RPRT
TI  - Map of coal-mining features, Allegheny County, Pennsylvania
AU  - W.E. Davies
AU  - J. S. Pomeroy
AU  - W. R. Kohl
PY  - 1976
DO  - 10.3133/mf685c
UR  - https://pubs.usgs.gov/publication/mf685C
ID  - mf685C
ER  -