@misc{indiciae3157800ba75d,
  title = {Forty-second annual report of the Director of the United States Geological Survey},
  author = {George Otis Smith},
  year = {1921},
  doi = {10.3133/ar42},
  url = {https://pubs.usgs.gov/publication/ar42},
  note = {Source identifier: ar42}
}