@misc{indiciae31b4fcb7622b,
  title = {Gravity observations by U.S. Geological Survey in Kentucky prior to October 1, 1961},
  author = {Joel S. Watkins},
  year = {1971},
  doi = {10.3133/70043275},
  url = {https://pubs.usgs.gov/publication/70043275},
  note = {Source identifier: 70043275}
}