@misc{indiciae57733660d1a6,
  title = {Abundance and distribution of thorium in the carbonatite stock at Iron Hill, Powderhorn District, Gunnison County, Colorado},
  author = {Theodore J. Armbrustmacher},
  year = {1979},
  doi = {10.3133/ofr79536},
  url = {https://pubs.usgs.gov/publication/ofr79536},
  note = {Source identifier: ofr79536}
}