@misc{indiciae44e3b022690b,
  title = {Preliminary report of the geology of the Barranquitas quadrangle, Puerto Rico},
  author = {R. P. Briggs and P. A. Gelabert},
  year = {1962},
  doi = {10.3133/i336},
  url = {https://pubs.usgs.gov/publication/i336},
  note = {Source identifier: i336}
}