@misc{indiciae9e5a11c5e168,
  title = {Determination of trace levels of herbicides and their degradation products in surface and ground waters by gas chromatography/ion-trap mass spectrometry},
  author = {W. E. Pereira and C.E. Rostad and T.J. Leiker},
  year = {1990},
  doi = {10.1016/s0003-2670(00)80480-8},
  url = {https://pubs.usgs.gov/publication/70016252},
  note = {Source identifier: 70016252}
}