@misc{indiciaece9ae8b4d6ea,
  title = {Determination of gold in waters in the nanogram range by anion exchange and atomic absorption spectrophotometry},
  author = {T. T. Chao},
  year = {1969},
  doi = {10.2113/gsecongeo.64.3.287},
  url = {https://pubs.usgs.gov/publication/70223814},
  note = {Source identifier: 70223814}
}