@misc{indiciaeaaf560450162,
  title = {Preliminary geologic map of the Bayamon quadrangle, Puerto Rico},
  author = {W. H. Monroe and M. H. Pease},
  year = {1962},
  doi = {10.3133/i347},
  url = {https://pubs.usgs.gov/publication/i347},
  note = {Source identifier: i347}
}