TY - RPRT TI - Potentiometric Surface of the Upper Floridan Aquifer in the St. Johns River Water Management District and Vicinity, Florida, May 2006 AU - Sandra L. Kinnaman PY - 2006 DO - 10.3133/ofr20061394 UR - https://pubs.usgs.gov/publication/ofr20061394 ID - ofr20061394 ER -