@misc{indiciae03d43766e5f0,
  title = {Average topography, isostatic residual gravity, and aeromagnetic maps of the Parkfield region, California},
  author = {Robert W. Simpson and R.C. Jachens and Carl M. Wentworth},
  year = {1989},
  doi = {10.3133/ofr8913},
  url = {https://pubs.usgs.gov/publication/ofr8913},
  note = {Source identifier: ofr8913}
}