@misc{indiciae7d57d9233592,
  title = {Map showing depth to bedrock, Guilford quadrangle, Connecticut},
  author = {M. H. Ginsberg},
  year = {1976},
  doi = {10.3133/mf583c},
  url = {https://pubs.usgs.gov/publication/mf583C},
  note = {Source identifier: mf583C}
}