@misc{indiciae70f3d08e9827,
  title = {Bouguer gravity anomaly map of Lake Superior},
  author = {R. J. Wold and J. M. Berkson},
  year = {1977},
  doi = {10.3133/mf884},
  url = {https://pubs.usgs.gov/publication/mf884},
  note = {Source identifier: mf884}
}