@misc{indiciaec7e9d04af5f3,
  title = {Use of nitrogen isotopes to determine sources of nitrate contamination in two desert basins in California},
  author = {J.N. Densmore and J.K. Bohlke},
  year = {1999},
  url = {https://pubs.usgs.gov/publication/70022103},
  note = {Source identifier: 70022103}
}