@misc{indiciae01f9a5c19533,
  title = {Geologic map and coal sections of the northern part of the Horse Hill quadrangle, Sheridan County, Wyoming},
  author = {W. J. Mapel},
  year = {1978},
  doi = {10.3133/ofr78793},
  url = {https://pubs.usgs.gov/publication/ofr78793},
  note = {Source identifier: ofr78793}
}