Mamoru Komachi Taku Kudo Masashi Shimbo Yuji Matsumoto Graph-based Analysis of Semantic Drift in Espresso-like Bootstrapping Algorithms. 1011-1020 2008 EMNLP http://www.aclweb.org/anthology/D08-1106 conf/emnlp/2008 db/conf/emnlp/emnlp2008.html#KomachiKSM08