@misc{indiciae98dcf5ee6143,
  title = {Preliminary bedrock geologic map of part of Durham quadrangle, Connecticut},
  author = {Howard E. Simpson},
  year = {1969},
  doi = {10.3133/ofr69257},
  url = {https://pubs.usgs.gov/publication/ofr69257},
  note = {Source identifier: ofr69257}
}