@misc{indiciae44777d54a886,
  title = {Geology and coal resources of the Ivydell quadrangle, Campbell County, Tennessee},
  author = {Kenneth John Englund},
  year = {1958},
  doi = {10.3133/coal40},
  url = {https://pubs.usgs.gov/publication/coal40},
  note = {Source identifier: coal40}
}