TY - RPRT TI - Potentiometric surface of the Floridan aquifer in the St. Johns River Water Management District and vicinity, Florida, September 1983 AU - G. R. Schiner AU - E. C. Hayes PY - 1983 DO - 10.3133/ofr83869 UR - https://pubs.usgs.gov/publication/ofr83869 ID - ofr83869 ER -