@misc{indiciae03dce120bf78,
  title = {Environmental tracers as indicators of karst conduits in groundwater in South Dakota, USA},
  author = {Andrew J. Long and J.F. Sawyer and L.D. Putnam},
  year = {2007},
  doi = {10.1007/s10040-007-0232-7},
  url = {https://pubs.usgs.gov/publication/70031726},
  note = {Source identifier: 70031726}
}