@misc{indiciae0b855e2bf8f4,
  title = {Gravity observations and bouguer anomaly values near Tucson, Arizona},
  author = {Donald Plouff},
  year = {1964},
  doi = {10.3133/ofr64124},
  url = {https://pubs.usgs.gov/publication/ofr64124},
  note = {Source identifier: ofr64124}
}