Terence R. Smith Jianwen Su Divyakant Agrawal Amr El Abbadi Database and Modeling Systems for the Earth Sciences. 33-37 1993 16 IEEE Data Eng. Bull. 1 DEBU/93MAR-CD.PDF db/journals/debu/debu16.html#SmithSAA93 db/journals/debu/SmithSAA93.html