@misc{indiciae4d3f6348bcfd,
  title = {Geology of the Penuelas and Punta Cuchara quadrangles, Puerto Rico},
  author = {R.D. Krushensky and Watson Hiner Monroe},
  year = {1977},
  doi = {10.3133/ofr77173},
  url = {https://pubs.usgs.gov/publication/ofr77173},
  note = {Source identifier: ofr77173}
}