TY - RPRT TI - Finite-difference model to simulate the areal flow of saltwater and fresh water separated by an interface AU - James W. Mercer AU - S. P. Larson AU - Charles R. Faust PY - 1980 DO - 10.3133/ofr80407 UR - https://pubs.usgs.gov/publication/ofr80407 ID - ofr80407 ER -