@misc{indiciaecd1dfadbbd61,
  title = {Pre-Cambrian geology and mineral resources of the Delaware Water Gap and Easton quadrangles, New Jersey and Pennsylvania},
  author = {William Shirley Bayley},
  year = {1941},
  doi = {10.3133/b920},
  url = {https://pubs.usgs.gov/publication/b920},
  note = {Source identifier: b920}
}