TY - RPRT TI - Potentiometric surface of the Aquia aquifer in southern Maryland, September 1997 AU - Stephen E. Curtin AU - David C. Andreasen AU - Frederick K. Mack PY - 1999 DO - 10.3133/ofr9982 UR - https://pubs.usgs.gov/publication/ofr9982 ID - ofr9982 ER -