title: the database group at university of hagen ( fernuniversitaet ). authors: silke mittrach , gunter schlageter , thomas berkel , andreas scherer , eberhard heuel , wolfgang wilkes. venue: sigmod record. year: 1995.0
title: the database group at national technical university of athens ( ntua ) corporate national technical univ. of athens. authors: nan. venue: acm sigmod record. year: 1995.0