title: database research at the university of oklahoma. authors: l gruenwald , l brown , r dirckze , s guinepain , c sсnchez , b summers , s vanichayobon. venue: sigmod record. year: 1999
title: database research at the university of illinois at urbana-champaign. authors: m winslett , kcc chang , ah doan , j han , c zhai , y. venue: sigmod record ,. year: 2002.0