@misc{indiciae4ab6592561ce,
  title = {Age and tectonic setting of lower Paleozoic alkalic and mafic rocks, carbonatites, and thorium veins in South-central Colorado},
  author = {Jerry C. Olson and Richard F. Marvin and Raymond Laurence Parker and Harald H. Mehnert},
  year = {1977},
  url = {https://pubs.usgs.gov/publication/70233484},
  note = {Source identifier: 70233484}
}