@misc{indiciae4098cc66d10d,
  title = {Volcanic ash dispersed in the Wyodak-Anderson coal bed, Powder River Basin, Wyoming},
  author = {Don M. Triplehorn and R.W. Stanton and Leslie F. Ruppert and Sharon S. Crowley},
  year = {1991},
  doi = {10.1016/0146-6380(91)90119-5},
  url = {https://pubs.usgs.gov/publication/70015609},
  note = {Source identifier: 70015609}
}