@misc{indiciaed9c047541ae5,
  title = {Design of the National Water-Quality Assessment Program; occurrence and distribution of water-quality conditions},
  author = {Robert J. Gilliom and William M. Alley and Martin E. Gurtz},
  year = {1995},
  doi = {10.3133/cir1112},
  url = {https://pubs.usgs.gov/publication/cir1112},
  note = {Source identifier: cir1112}
}