@misc{indiciae2695cef6e348,
  title = {Aeromagnetic map of northwestern Illinois},
  author = {Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey},
  year = {1982},
  doi = {10.3133/ofr82190},
  url = {https://pubs.usgs.gov/publication/ofr82190},
  note = {Source identifier: ofr82190}
}