@misc{indiciaecf5a4a30fb18,
  title = {What is ground water?},
  author = {David W. Clark and David W. Briar},
  year = {1993},
  doi = {10.3133/ofr93643},
  url = {https://pubs.usgs.gov/publication/ofr93643},
  note = {Source identifier: ofr93643}
}