@misc{indiciaed8f9e0b0c17c,
  title = {Summary of United States mineral resources},
  author = {Donald Albert Brobst and Walden P. Pratt and V.E. McKelvey},
  year = {1973},
  doi = {10.3133/cir682},
  url = {https://pubs.usgs.gov/publication/cir682},
  note = {Source identifier: cir682}
}