@misc{indiciae2814cc98e61a,
  title = {Aeromagnetic map of Pennsylvania},
  author = {Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey},
  year = {1978},
  doi = {10.3133/gp924},
  url = {https://pubs.usgs.gov/publication/gp924},
  note = {Source identifier: gp924}
}