Andreas Billig Jan Gottschick Kurt Sandkuhl Evolution of Web Computing Systems: Experiences from Web-Portal Projects. 468-474 2005 conf/euromicro/2005 EUROMICRO-SEAA http://doi.ieeecomputersociety.org/10.1109/EURMIC.2005.27 db/conf/euromicro/euromicro2005.html#BilligGS05