@misc{indiciae50b4883a7ff7,
  title = {National Water-Quality Assessment (NAWQA) Study-Unit Investigations in the conterminous United States 2001-2012},
  author = {K.J. Hitt and N. Nakagaki},
  year = {2006},
  doi = {10.3133/70046918},
  url = {https://pubs.usgs.gov/publication/70046918},
  note = {Source identifier: 70046918}
}