TY  - RPRT
TI  - Water-level contour maps of the carbonate rocks of the Great Valley in Lehigh County, Pennsylvania
AU  - H.N. Flippo
AU  - C. R. Wood
PY  - 1969
DO  - 10.3133/ofr6993
UR  - https://pubs.usgs.gov/publication/ofr6993
ID  - ofr6993
ER  -