@misc{indiciaecd2aa73e47f9,
  title = {Analytical methods for chemical analysis of geologic and other materials, U.S. Geological Survey},
  year = {2002},
  doi = {10.3133/ofr02223},
  url = {https://pubs.usgs.gov/publication/ofr02223},
  note = {Source identifier: ofr02223}
}