@misc{indiciae20161b339081,
  title = {Relation of mineralization to calderas in the San Juan volcanic field, southwestern Colorado},
  author = {Thomas A. Steven and Robert G. Luedke and Peter W. Lipman},
  year = {1974},
  url = {https://pubs.usgs.gov/publication/70232457},
  note = {Source identifier: 70232457}
}