@misc{indiciae3116201ab65f,
  title = {Geology and ground-water resources of Puerto Rico},
  author = {Charles Lee McGuinness},
  year = {1947},
  doi = {10.2113/gsecongeo.42.6.563},
  url = {https://pubs.usgs.gov/publication/70206576},
  note = {Source identifier: 70206576}
}