@misc{indiciae3329e09444e2,
  title = {The structure and stratigraphy of the Pen Argyl Member of the Martinsburg Formation in Lehigh and Berks counties, Pennsylvania},
  author = {Gary George Lash},
  year = {1978},
  doi = {10.3133/ofr78391},
  url = {https://pubs.usgs.gov/publication/ofr78391},
  note = {Source identifier: ofr78391}
}