@misc{indiciaefcaae5824def,
  title = {Thickness and lithology of Upper Devonian and Carboniferous rocks in Michigan},
  author = {G. V. Cohee and Carol Macha and Margery Holk},
  year = {1951},
  doi = {10.3133/oc41},
  url = {https://pubs.usgs.gov/publication/oc41},
  note = {Source identifier: oc41}
}