@misc{indiciae3757457a76ab,
  title = {Preliminary geologic map showing iron and copper prospects in the Juncos quadrangle, Puerto Rico},
  author = {C.H. Broedel},
  year = {1961},
  doi = {10.3133/i326},
  url = {https://pubs.usgs.gov/publication/i326},
  note = {Source identifier: i326}
}