@misc{indiciae22b2bfb06a18,
  title = {Concentration method for the spectrochemical determination of minor elements in water},
  author = {William D. Silvery},
  year = {1961},
  doi = {10.3133/wsp1540b},
  url = {https://pubs.usgs.gov/publication/wsp1540B},
  note = {Source identifier: wsp1540B}
}