@misc{indiciaef5fe7d9e98c9,
  title = {Principal facts for gravity observations in Harold D. Roberts Tunnel, Colorado and the effect of isostasy},
  author = {Donald Plouff},
  year = {1985},
  doi = {10.3133/ofr85506},
  url = {https://pubs.usgs.gov/publication/ofr85506},
  note = {Source identifier: ofr85506}
}