@misc{indiciae76427a7f40c9,
  title = {Porphyry copper deposits of the world: Database, maps, and preliminary analysis},
  author = {Donald A. Singer and Vladimir I. Berger and Barry C. Moring},
  year = {2002},
  doi = {10.3133/ofr02268},
  url = {https://pubs.usgs.gov/publication/ofr02268},
  note = {Source identifier: ofr02268}
}