@misc{indiciaea42290e62aa5,
  title = {Nitrogen isotopes in nitrate from surface water and shallow groundwater at Sixmile Creek, southeastern Colorado},
  author = {Craig A. Johnson and Robert A. Zielinski and Sigrid A. Asher-Bolinder},
  year = {1995},
  doi = {10.3133/ofr95536},
  url = {https://pubs.usgs.gov/publication/ofr95536},
  note = {Source identifier: ofr95536}
}