@misc{indiciae9d05e304a0b8,
  title = {Forty-eighth annual report of the Director of the Geological Survey},
  author = {George Otis Smith},
  year = {1927},
  doi = {10.3133/ar48},
  url = {https://pubs.usgs.gov/publication/ar48},
  note = {Source identifier: ar48}
}