@misc{indiciae9ae90a0b0001,
  title = {Forty-ninth annual report of the Director of the Geological Survey},
  author = {George Otis Smith},
  year = {1928},
  doi = {10.3133/ar49},
  url = {https://pubs.usgs.gov/publication/ar49},
  note = {Source identifier: ar49}
}