Sonajharia Minz Rajni Jain Refining decision tree classifiers using rough set tools . 133-148 2005 2 Int. J. Hybrid Intell. Syst. 2 http://iospress.metapress.com/openurl.asp?genre=article&issn=1448-5869&volume=2&issue=2&spage=133 db/journals/ijhis/ijhis2.html#MinzJ05