@misc{indiciae635e396bad9c,
  title = {Gravity survey in parts of Maricopa and Pinal counties, Arizona},
  author = {Jerry H. Hassemer and Danny A. Dansereau},
  year = {1980},
  doi = {10.3133/ofr801255},
  url = {https://pubs.usgs.gov/publication/ofr801255},
  note = {Source identifier: ofr801255}
}