@misc{indiciae09cdd57e943d,
  title = {Geology of the Tanama and Helecho porphyry copper deposits and vicinity, Puerto Rico},
  author = {D. P. Cox},
  year = {1985},
  doi = {10.3133/pp1327},
  url = {https://pubs.usgs.gov/publication/pp1327},
  note = {Source identifier: pp1327}
}