@misc{indiciaef23ce9b45681,
  title = {Report on the U.S. Geological Survey's evaluation program for standard reference samples distributed in October 1992, T-121 (trace constituents), M-124 (major constituents), N-36 (nutrients), N-37 (nutrients), P-19 (low ionic strength) and Hg-15 (mercury)},
  author = {H.K. Long and J.W. Farrar},
  year = {1993},
  doi = {10.3133/ofr9332},
  url = {https://pubs.usgs.gov/publication/ofr9332},
  note = {Source identifier: ofr9332}
}