@INPROCEEDINGS{ZRH01, author = {W.P. Zhang and Norbert Ritter and Theo Härder}, title = {Enriched Relationship Processing in Object-Relational Database Management Systems}, booktitle = {Proc. 3rd Int. Symposium on Cooperative Database Systems for Advanced Applications (CODAS'01)}, year = {2001}, pages = {53-62}, month = {4} }