@misc{indiciaec3ce3ce20200,
  title = {The Sentinel Butte lignite field, North Dakota and Montana. The Miles City coal field, Montana. The Bull Mountain coal field, Montana. Coal near the Crazy Mountains, Montana. The Red Lodge coal field, Montana. The Lewistown coal field, Montana},
  author = {M. R. Campbell and Arthur J. Collier and Carl D. Smith and L.H. Woolsey and R.W. Stone and W. R. Calvert},
  year = {1909},
  doi = {10.3133/b341a},
  url = {https://pubs.usgs.gov/publication/b341A},
  note = {Source identifier: b341A}
}