@misc{indiciae096743e202f3,
  title = {Concepts for a National Water-Quality Assessment Program},
  author = {Robert M. Hirsch and William M. Alley and William G. Wilber},
  year = {1988},
  doi = {10.3133/cir1021},
  url = {https://pubs.usgs.gov/publication/cir1021},
  note = {Source identifier: cir1021}
}