@misc{indiciaef1ebc588c424,
  title = {Porphyry copper deposits in Puerto Rico and their relation to arc-trench tectonics},
  author = {Dennis P. Cox},
  year = {1973},
  doi = {10.3133/ofr7351},
  url = {https://pubs.usgs.gov/publication/ofr7351},
  note = {Source identifier: ofr7351}
}