@misc{indiciae0709cd114131,
  title = {Maps showing anomalous copper concentrations in stream sediments and heavy-mineral concentrates from the Ajo and Lukeville 1 degree by 2 degrees quadrangles, Arizona},
  author = {P. K. Theobald and H. N. Barton},
  year = {1987},
  doi = {10.3133/mf1834c},
  url = {https://pubs.usgs.gov/publication/mf1834C},
  note = {Source identifier: mf1834C}
}