@misc{indiciae9516d144c808,
  title = {Airborne electromagnetic and magnetic survey of parts of the Upper Peninsula of Michigan and Northern Wisconsin},
  author = {Geoterrex Limited and William D. Heran},
  year = {1981},
  doi = {10.3133/ofr81577a},
  url = {https://pubs.usgs.gov/publication/ofr81577A},
  note = {Source identifier: ofr81577A}
}