@misc{indiciae704a515823ae,
  title = {Bedrock geologic map of the Hampden quadrangle, Massachusetts and Connecticut},
  author = {J. D. Peper},
  year = {1974},
  doi = {10.3133/ofr7461},
  url = {https://pubs.usgs.gov/publication/ofr7461},
  note = {Source identifier: ofr7461}
}