@misc{indiciae6cde66c2a81a,
  title = {Geologic map of Isle Royale National Park, Keweenaw County, Michigan},
  author = {N.K. Huber},
  year = {1973},
  doi = {10.3133/i796},
  url = {https://pubs.usgs.gov/publication/i796},
  note = {Source identifier: i796}
}