TY  - RPRT
TI  - Design of the National Water-Quality Assessment Program; occurrence and distribution of water-quality conditions
AU  - Robert J. Gilliom
AU  - William M. Alley
AU  - Martin E. Gurtz
PY  - 1995
DO  - 10.3133/cir1112
UR  - https://pubs.usgs.gov/publication/cir1112
ID  - cir1112
ER  -