@misc{indiciae34d77fbb73e3,
  title = {Preliminary design study for a National Digital Seismograph Network},
  author = {Jon Peterson and Charles R. Hutt},
  year = {1981},
  doi = {10.3133/ofr811046},
  url = {https://pubs.usgs.gov/publication/ofr811046},
  note = {Source identifier: ofr811046}
}