TY  - RPRT
TI  - Automated, colorimetric methods for determination of nitrate plus nitrite, nitrite, ammonium and orthophosphate ions in natural water samples
AU  - Ronald C. Antweiler
AU  - Charles J. Patton
AU  - Howard E. Taylor
PY  - 1996
DO  - 10.3133/ofr93638
UR  - https://pubs.usgs.gov/publication/ofr93638
ID  - ofr93638
ER  -