@misc{indiciae57cc8824e3c6,
  title = {Geologic map of the Keweenaw Peninsula and adjacent area, Michigan},
  author = {W.F. Cannon and S. W. Nicholson},
  year = {2001},
  doi = {10.3133/i2696},
  url = {https://pubs.usgs.gov/publication/i2696},
  note = {Source identifier: i2696}
}