TY  - RPRT
TI  - Chapter A6. Section 6.4. pH
AU  - George F. Ritz
AU  - J. A. Collins
PY  - 2008
DO  - 10.3133/twri09a6.4
UR  - https://pubs.usgs.gov/publication/twri09A6.4
ID  - twri09A6.4
ER  -