@misc{indiciaee23bfbb93941,
  title = {Map and list of reported occurrences of platinum-group metals in the conterminous United States},
  author = {W.N. Blair and N.J. Page and M. G. Johnson},
  year = {1977},
  doi = {10.3133/mf861},
  url = {https://pubs.usgs.gov/publication/mf861},
  note = {Source identifier: mf861}
}