@misc{indiciae7caef153fec6,
  title = {Surficial geologic map of part of the Allentown 30' x 60' quadrangle, Berks, Bucks, Carbon, Lehigh, Luzerne, Monroe, Northampton, and Schuylkill Counties, Pennsylvania},
  author = {D. D. Braun and J. B. Epstein},
  year = {1993},
  doi = {10.3133/ofr93723},
  url = {https://pubs.usgs.gov/publication/ofr93723},
  note = {Source identifier: ofr93723}
}