@misc{indiciae7eab3cc31aa0,
  title = {Geologic map of the Mount Carmel quadrangle, Columbia, Northumberland, and Schuylkill Counties, Pennsylvania},
  author = {Harold H. Arndt},
  year = {1971},
  doi = {10.3133/gq919},
  url = {https://pubs.usgs.gov/publication/gq919},
  note = {Source identifier: gq919}
}