@misc{indiciaeae0450613021,
  title = {Determination of the delta(15N/14N)of Ammonium (NH4+) in Water: RSIL Lab Code 2898},
  author = {Janet E. Hannon and John Karl Böhlke},
  year = {2008},
  doi = {10.3133/tm10c15},
  url = {https://pubs.usgs.gov/publication/tm10C15},
  note = {Source identifier: tm10C15}
}