title: on the issue of valid time ( s ) in temporal databases. authors: themis panayiotopoulos , efstathios v. ioannidis , constantine d. spyropoulos , stavros kokkotos. venue: sigmod record. year: 1995
title: semantic assumptions and query evaluation in temporal databases. authors: claudio bettini , x. sean wang , elisa bertino , sushil jajodia. venue: international conference on management of data. year: 1995