TY  - RPRT
TI  - Variability of nitrate concentrations in the shallow ground water in a selected area of the San Luis Valley, south-central Colorado
AU  - Stogner
PY  - 1997
DO  - 10.3133/fs00497
UR  - https://pubs.usgs.gov/publication/fs00497
ID  - fs00497
ER  -