Simona Colucci Eugenio Di Sciascio Francesco M. Donini Eufemia Tinelli Finding informative commonalities in concept collections. 807-817 2008 CIKM http://doi.acm.org/10.1145/1458082.1458190 conf/cikm/2008 db/conf/cikm/cikm2008.html#ColucciSDT08