@misc{indiciae01a150009968,
  title = {Geologic map of the Rio Descalabrado Quadrangle, Puerto Rico},
  author = {Lynn Glover and P.H. Mattson},
  year = {1973},
  doi = {10.3133/i735},
  url = {https://pubs.usgs.gov/publication/i735},
  note = {Source identifier: i735}
}