@misc{indiciaef57e3b818657,
  title = {Copper in the United States, exclusive of Alaska and Hawaii},
  author = {Arthur R. Kinkel and N. P. Peterson},
  year = {1962},
  doi = {10.3133/mr13},
  url = {https://pubs.usgs.gov/publication/mr13},
  note = {Source identifier: mr13}
}