@misc{indiciaee1c58db4e669,
  title = {Type sections of the Madison Group (Mississippian) and its subdivisions in Montana},
  author = {William Jasper Sando and J. Thomas Dutro},
  year = {1974},
  doi = {10.3133/pp842},
  url = {https://pubs.usgs.gov/publication/pp842},
  note = {Source identifier: pp842}
}