@misc{indiciae18d3c3ee6007,
  title = {Simple Bouguer gravity map of Maine},
  author = {M. F. Kane and R. W. Bromery},
  year = {1966},
  doi = {10.3133/gp580},
  url = {https://pubs.usgs.gov/publication/gp580},
  note = {Source identifier: gp580}
}