@misc{indiciaed6e9d7bf36db,
  title = {Middle tertiary volcanic field in the southern Rocky Mountains},
  author = {T. A. Steven},
  year = {1975},
  doi = {10.1130/mem144-p75},
  url = {https://pubs.usgs.gov/publication/70206954},
  note = {Source identifier: 70206954}
}