@misc{indiciae0e92e73ba0fa,
  title = {Bouguer gravity anomaly map of the Twin Buttes area, Pima and Santa Cruz Counties, Arizona},
  author = {Donald Plouff},
  year = {1962},
  doi = {10.3133/ofr62104},
  url = {https://pubs.usgs.gov/publication/ofr62104},
  note = {Source identifier: ofr62104}
}