Elaheh Pourabbas Arie Shoshani The Composite OLAP-Object Data Model: Removing an Unnecessary Barrier. 291-300 2006 conf/ssdbm/2006 SSDBM http://doi.ieeecomputersociety.org/10.1109/SSDBM.2006.50 db/conf/ssdbm/ssdbm2006.html#PourabbasS06