@misc{indiciae100371fdd5a5,
  title = {Mineral resource potential of the Hunter-Fryingpan Wilderness and the Porphyry Mountain Wilderness Study Area, Pitkin County, Colorado},
  author = {Steve Ludington and Clarence E. Ellis},
  year = {1981},
  doi = {10.3133/mf1236d},
  url = {https://pubs.usgs.gov/publication/mf1236D},
  note = {Source identifier: mf1236D}
}