@misc{indiciae8610f5d29a5c,
  title = {Geology and ore deposits of the Leadville mining district, Colorado},
  author = {S. F. Emmons and J.D. Irving and G. F. Loughlin},
  year = {1927},
  doi = {10.3133/pp148},
  url = {https://pubs.usgs.gov/publication/pp148},
  note = {Source identifier: pp148}
}