@misc{indiciae07fb369ae8db,
  title = {USGS Blind Sample Project: monitoring and evaluating laboratory analytical quality},
  author = {Amy S. Ludtke and Mark T. Woodworth},
  year = {1997},
  doi = {10.3133/fs13697},
  url = {https://pubs.usgs.gov/publication/fs13697},
  note = {Source identifier: fs13697}
}