Nguyen Thanh Thuy Duong Hieu Phan Takahiro Yamanoi Some Preliminary Results on the Stableness of Extended F-rule Systems. 252-259 2003 7 JACIII 3 http://www.fujipress.jp/finder/xslt.php?mode=present&inputfile=JACII000700030001.xml db/journals/jaciii/jaciii7.html#ThuyHY03