Mario Boley Tamás Horváth Stefan Wrobel Efficient Discovery of Interesting Patterns Based on Strong Closedness. 1002-1013 2009 SDM http://www.siam.org/proceedings/datamining/2009/dm09_091_boleym.pdf conf/sdm/2009 db/conf/sdm/sdm2009.html#BoleyHW09