TY  - RPRT
TI  - Methodology to derive water-quality trends for use by the National Water Summary Program of the U.S. Geological Survey
AU  - K.J. Lanfear
AU  - R. Alexander
PY  - 1990
DO  - 10.3133/ofr90359
UR  - https://pubs.usgs.gov/publication/ofr90359
ID  - ofr90359
ER  -