@misc{indiciaeee98b53007f2,
  title = {N-15 NMR spectra of naturally abundant nitrogen in soil and aquatic natural organic matter samples of the International Humic Substances Society},
  author = {K. A. Thorn and L.G. Cox},
  year = {2009},
  doi = {10.1016/j.orggeochem.2009.01.007},
  url = {https://pubs.usgs.gov/publication/70035002},
  note = {Source identifier: 70035002}
}