Christopher Popfinger Cristian Pérez de Laborda Stefan Conrad Link Patterns for Modeling Information Grids and P2P Networks. 388-401 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3288&spage=388 2004 conf/er/2004 ER db/conf/er/er2004.html#PopfingerLC04