TY  - RPRT
TI  - Methods of analysis by the U. S. Geological Survey National Water Quality Laboratory-Determination of organonitrogen herbicides in water by solid-phase extraction and capillary-column gas chromatography/mass spectrometry with selected-ion monitoring
AU  - Mark W. Sandstrom
AU  - Duane S. Wydoski
AU  - Michael P. Schroeder
AU  - Jana L. Zamboni
AU  - William T. Foreman
PY  - 1992
DO  - 10.3133/ofr91519
UR  - https://pubs.usgs.gov/publication/ofr91519
ID  - ofr91519
ER  -