@misc{indiciae30a1867e4d1d,
  title = {Geologic map of the Mather quadrangle, southwestern Pennsylvania},
  author = {Bion H. Kent},
  year = {1969},
  doi = {10.3133/gq826},
  url = {https://pubs.usgs.gov/publication/gq826},
  note = {Source identifier: gq826}
}