@misc{indiciae3016aaa5cb30,
  title = {Bedrock geology of the Millers Falls quadrangle, Massachusetts},
  author = {Robert Balk},
  year = {1956},
  doi = {10.3133/gq93},
  url = {https://pubs.usgs.gov/publication/gq93},
  note = {Source identifier: gq93}
}