Yunjiao Xue Chun Wang Hamada Ghenniwa Weiming Shen A new tree similarity measuring method and its application to ontology comparison. 258-263 2008 CSCWD http://dx.doi.org/10.1109/CSCWD.2008.4536991 conf/cscwd/2008 db/conf/cscwd/cscwd2008.html#XueWGS08