Yoshiaki Okubo Makoto Haraguchi Finding Top-<i>N</i> Pseudo Formal Concepts with Core Intents. 479-493 2009 MLDM http://dx.doi.org/10.1007/978-3-642-03070-3_36 conf/mldm/2009 db/conf/mldm/mldm2009.html#OkuboH09