@misc{indiciae2a5423da8cc8,
  title = {Field spectroanalytical laboratory for servicing prospecting parties},
  author = {E.A. Ratsbaum and V.P. Sokoloff},
  year = {1939},
  doi = {10.3133/ofr4821a},
  url = {https://pubs.usgs.gov/publication/ofr4821A},
  note = {Source identifier: ofr4821A}
}