@misc{indiciaeced916e40bd3,
  title = {The Elliston phosphate field, Montana},
  author = {R.W. Stone and C. A. Bonine},
  year = {1915},
  doi = {10.3133/b580n},
  url = {https://pubs.usgs.gov/publication/b580N},
  note = {Source identifier: b580N}
}