@misc{indiciae8134878fed52,
  title = {Preliminary geologic and structural maps and sections of the Marshall Pass Mining District, Saguache, Gunnison, and Chaffee counties, Colorado},
  author = {J. C. Olson},
  year = {1979},
  doi = {10.3133/ofr791473},
  url = {https://pubs.usgs.gov/publication/ofr791473},
  note = {Source identifier: ofr791473}
}