@misc{indiciae3551ff9fe0fb,
  title = {Preliminary geologic map of the Cerro Cobachi area, Sonora, Mexico},
  author = {K. B. Ketner and J.H. Noll},
  year = {1987},
  doi = {10.3133/mf1980},
  url = {https://pubs.usgs.gov/publication/mf1980},
  note = {Source identifier: mf1980}
}