@misc{indiciaeef24da17b820,
  title = {Maps showing thickness and general distribution of Mesozoic and Paleozoic rocks in south-central Montana},
  author = {C.P. Rogers and L.S. Gardner and Herbert D. Hadley},
  year = {1945},
  doi = {10.3133/om43},
  url = {https://pubs.usgs.gov/publication/om43},
  note = {Source identifier: om43}
}