@misc{indiciaeee6ed21bdded,
  title = {Preliminary geologic map and coal sections, ULM Quadrangle, Sheridan County, Wyoming},
  author = {W. J. Mapel and B.W. Dean},
  year = {1976},
  doi = {10.3133/mf731},
  url = {https://pubs.usgs.gov/publication/mf731},
  note = {Source identifier: mf731}
}