@misc{indiciae6dedc92c8099,
  title = {A description of colored isostatic gravity maps and a topographic map of the conterminous United States},
  author = {R.W. Simpson and R. W. Saltus and R.C. Jachens and R. H. Godson},
  year = {1983},
  doi = {10.3133/ofr83884},
  url = {https://pubs.usgs.gov/publication/ofr83884},
  note = {Source identifier: ofr83884}
}