@misc{indiciae3b9034c5858f,
  title = {A new method for collection of nitrate from fresh water and the analysis of nitrogen and oxygen isotope ratios},
  author = {S. R. Silva and C. Kendall and D.H. Wilkison and A.C. Ziegler and Cecily C.Y. Chang and R.J. Avanzino},
  year = {2000},
  doi = {10.1016/s0022-1694(99)00205-x},
  url = {https://pubs.usgs.gov/publication/70022921},
  note = {Source identifier: 70022921}
}