@misc{indiciae376be8da5a96,
  title = {Map showing distribution, composition, and age of late Cenozoic volcanic centers in Colorado, Utah, and southwestern Wyoming},
  author = {R. G. Luedke and R. L. Smith},
  year = {1978},
  doi = {10.3133/i1091b},
  url = {https://pubs.usgs.gov/publication/i1091B},
  note = {Source identifier: i1091B}
}