Toshiko Wakaki Hiroyuki Itakura Masaki Tamura Hiroshi Motoda Takashi Washio A study on rough set-aided feature selection for automatic web-page classification. 431-441 2006 4 Web Intelligence and Agent Systems 4 http://iospress.metapress.com/openurl.asp?genre=article&issn=1570-1263&volume=4&issue=4&spage=431 db/journals/wias/wias4.html#WakakiITMW06