TY  - RPRT
TI  - Are shifts in herbicide use reflected in concentration changes in Midwestern rivers?
AU  - W.A. Battaglin
AU  - D. A. Goolsby
PY  - 1999
DO  - 10.1021/es9900149
UR  - https://pubs.usgs.gov/publication/70021522
ID  - 70021522
ER  -