@misc{indiciae6fea4d8a7438,
  title = {Geology and resources of fluorine in the United States},
  author = {R. E. Van Alstine and R. G. Worl and A. V. Heyl and R. D. Trace and R. L. Parker and W. R. Griffitts and C.L. Sainsbury and J.B. Cathcart},
  year = {1976},
  doi = {10.3133/pp933},
  url = {https://pubs.usgs.gov/publication/pp933},
  note = {Source identifier: pp933}
}