@misc{indiciae3f64829ae803,
  title = {Potash feldspar of possible economic value in the Barstow Formation, San Bernardino County, California},
  author = {Richard A. Sheppard and Arthur J. Gude},
  year = {1965},
  doi = {10.3133/cir500},
  url = {https://pubs.usgs.gov/publication/cir500},
  note = {Source identifier: cir500}
}