@misc{indiciae2a3d87c8964f,
  title = {The Belt series in Montana, with a geologic map and a section on paleontologic criteria},
  author = {Clyde Polhemus Ross and B.A.L. Skipp and Richard Rezak},
  year = {1963},
  doi = {10.3133/pp346},
  url = {https://pubs.usgs.gov/publication/pp346},
  note = {Source identifier: pp346}
}