@misc{indiciae42a2173ffa54,
  title = {Secondary hydrogeologic regions of the conterminous United States},
  author = {Kenneth Belitz and Elise Watson and Tyler D. Johnson and Jennifer B. Sharpe},
  year = {2018},
  doi = {10.1111/gwat.12806},
  url = {https://pubs.usgs.gov/publication/70198156},
  note = {Source identifier: 70198156}
}