@misc{indiciae91bf621cdbc4,
  title = {Geologic map of the Hillsboro and San Lorenzo Quadrangle, Sierra and Grant counties, New Mexico},
  author = {D. C. Hedlund},
  year = {1977},
  doi = {10.3133/mf900a},
  url = {https://pubs.usgs.gov/publication/mf900A},
  note = {Source identifier: mf900A}
}