Luca Cabibbo Roberto Porcelli M<sup>2</sup>ORM<sup>2</sup>: A Model for the Transparent Management of Relationally Persistent Objects. 166-178 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2921&spage=166 2003 conf/dbpl/2003 DBPL db/conf/dbpl/dbpl2003.html#CabibboP03