@misc{indiciae60f9218740c2,
  title = {A modification of mineral mapping program (G239)},
  author = {Jocelyn A. Peterson},
  year = {1977},
  doi = {10.3133/ofr77713},
  url = {https://pubs.usgs.gov/publication/ofr77713},
  note = {Source identifier: ofr77713}
}