@misc{indiciae9684aa24f881,
  title = {Map showing thickness of principal clay unit, Hartford South Quadrangle, Connecticut},
  author = {William H. Langer},
  year = {1974},
  doi = {10.3133/mf487b},
  url = {https://pubs.usgs.gov/publication/mf487B},
  note = {Source identifier: mf487B}
}