@misc{indiciae8bf34c295c06,
  title = {The oxidized zinc ores of Leadville, Colorado},
  author = {G. F. Loughlin},
  year = {1918},
  doi = {10.3133/b681},
  url = {https://pubs.usgs.gov/publication/b681},
  note = {Source identifier: b681}
}