@misc{indiciae40c4afb2de05,
  title = {Stratigraphy of Mid-Cretaceous Blackleaf and lower part of the Frontier formations in parts of Beaverhead and Madison counties, Montana},
  author = {T. S. Dyman and D. J. Nichols},
  year = {1988},
  doi = {10.3133/b1773},
  url = {https://pubs.usgs.gov/publication/b1773},
  note = {Source identifier: b1773}
}