Enrico Franconi Anand Kamble The GMD Data Model and Algebra for Multidimensional Information. 446-462 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3084&spage=446 2004 conf/caise/2004 CAiSE db/conf/caise/caise2004.html#FranconiK04