@misc{indiciae773d23ef404e,
  title = {Colorado vermiculite deposits: mines, prospects, and occurrences},
  author = {Bradley S. VanGosen and Alfred L. Bush},
  year = {2001},
  doi = {10.3133/ofr01475},
  url = {https://pubs.usgs.gov/publication/ofr01475},
  note = {Source identifier: ofr01475}
}