@misc{indiciaef4de7bd9f2f1,
  title = {Aeromagnetic map of the northwestern part of Cook County, Minnesota},
  author = {L. A. Anderson and N.S. Tyson},
  year = {1963},
  doi = {10.3133/gp361},
  url = {https://pubs.usgs.gov/publication/gp361},
  note = {Source identifier: gp361}
}