Tatsuya Asai Kenji Abe Shinji Kawasoe Hiroki Arimura Hiroshi Sakamoto Setsuo Arikawa Efficient Substructure Discovery from Large Semi-structured Data. 2002 conf/sdm/2002 SDM http://www.siam.org/meetings/sdm02/proceedings/sdm02-10.pdf db/conf/sdm/sdm2002.html#AsaiAKASA02