TY  - RPRT
TI  - Index to water-quality data available from the U.S. Geological Survey in machine-readable form to December 31, 1972-Central Region
AU  - C.R. Showen
AU  - O.O. Williams
PY  - 1973
DO  - 10.3133/wri7323
UR  - https://pubs.usgs.gov/publication/wri7323
ID  - wri7323
ER  -