TY - RPRT TI - The difference between the potentiometric surfaces of the upper Patapsco aquifer, September 1990 and September 2003 in southern Maryland AU - Stephen E. Curtin AU - David C. Andreasen AU - Judith C. Wheeler PY - 2005 DO - 10.3133/ofr20051009 UR - https://pubs.usgs.gov/publication/ofr20051009 ID - ofr20051009 ER -