@misc{indiciaedb8fb46102cb,
  title = {Preliminary geologic map of the Salinas quadrangle, Puerto Rico},
  author = {Lynn Glover},
  year = {1961},
  doi = {10.3133/i337},
  url = {https://pubs.usgs.gov/publication/i337},
  note = {Source identifier: i337}
}