@misc{indiciae892834f86f73,
  title = {Lithologic, geophysical, and mineral commodity maps of Precambrian rocks in Wisconsin},
  author = {C. E. Dutton and R. E. Bradley},
  year = {1970},
  doi = {10.3133/i631},
  url = {https://pubs.usgs.gov/publication/i631},
  note = {Source identifier: i631}
}