@misc{indiciae722158e9d047,
  title = {Oxidized zinc deposits of the United States: Part 3. Colorado},
  author = {A. V. Heyl},
  year = {1964},
  doi = {10.3133/b1135c},
  url = {https://pubs.usgs.gov/publication/b1135C},
  note = {Source identifier: b1135C}
}