@misc{indiciae4584f1725f9e,
  title = {Mineral resources of the United States, 1915: Part II - Nonmetals},
  author = {Hiram Dryer McCaskey and Ernest Francis Burchard},
  year = {1917},
  doi = {10.3133/70175815},
  url = {https://pubs.usgs.gov/publication/70175815},
  note = {Source identifier: 70175815}
}