@misc{indiciaede042764dba8,
  title = {Principal facts for gravity stations in Safford and San Simon Valleys, Arizona},
  author = {G. P. Eaton and C.E. Timmons},
  year = {1966},
  doi = {10.3133/ofr6640},
  url = {https://pubs.usgs.gov/publication/ofr6640},
  note = {Source identifier: ofr6640}
}