@misc{indiciaeaea56fd13b6a,
  title = {Geology of the Mayagüez area, Puerto Rico},
  author = {Peter H. Mattson},
  year = {1960},
  doi = {10.1130/0016-7606(1960)71[319:gotmap]2.0.co;2},
  url = {https://pubs.usgs.gov/publication/70220580},
  note = {Source identifier: 70220580}
}