TY  - RPRT
TI  - A national look at nitrate contamination of ground water
AU  - Bernard T. Nolan
AU  - Barbara C. Ruddy
AU  - Kerie J. Hitt
AU  - Dennis R. Helsel
PY  - 1998
UR  - https://pubs.usgs.gov/publication/70046294
ID  - 70046294
ER  -