title: the algres testbed of chimera : an active object-oriented database system. authors: giuseppe psaila , stefano ceri , stefano paraboschi , piero fraternali. venue: sigmod conference. year: 1995
title: the trigs active object-oriented database system - an overview. authors: g. kappel , w. retschitzegger. venue: acm sigmod record. year: 1998