Hajime Sawamura Toshiko Wakaki Katsumi Nitta The Logic of Multiple-Valued Argumentation and its Applications to Web Technology - Extended Abstract. 291-296 2006 COMMA http://www.booksonline.iospress.nl/Content/View.aspx?piid=1950 conf/comma/2006 db/conf/comma/comma2006.html#SawamuraWN06