@misc{indiciae930a424138ff,
  title = {Occurrence of platinum in a black sand from a beach deposit in San Mateo County, California},
  author = {Gretchen Luepke and Norman M. Maher},
  year = {1991},
  doi = {10.3133/ofr91308},
  url = {https://pubs.usgs.gov/publication/ofr91308},
  note = {Source identifier: ofr91308}
}