@misc{indiciae266b22c7741b,
  title = {Economic geology of the Amity quadrangle, eastern Washington County, Pennsylvania},
  author = {Frederick Gardner Clapp},
  year = {1907},
  doi = {10.3133/b300},
  url = {https://pubs.usgs.gov/publication/b300},
  note = {Source identifier: b300}
}