@misc{indiciae1418315338b4,
  title = {Determination of nanogram levels of silver in suspended materials of streams retained by a membrane filter with the "sampling-boat" technique},
  author = {T. T. Chao and J.W. Ball},
  year = {1971},
  doi = {10.1016/s0003-2670(01)81871-7},
  url = {https://pubs.usgs.gov/publication/70009777},
  note = {Source identifier: 70009777}
}