@misc{indiciaeb21bdce2b0b8,
  title = {Ion exchange capture of copper, lead, and zinc in acid-rock drainages of Colorado using natural clinoptilolite; preliminary field studies},
  author = {G. A. Desborough},
  year = {1992},
  doi = {10.3133/ofr92614},
  url = {https://pubs.usgs.gov/publication/ofr92614},
  note = {Source identifier: ofr92614}
}