@misc{indiciae791db8cc84c4,
  title = {Geologic map of the Tucson Mountains Caldera, southern Arizona},
  author = {P. W. Lipman},
  year = {1993},
  doi = {10.3133/i2205},
  url = {https://pubs.usgs.gov/publication/i2205},
  note = {Source identifier: i2205}
}