Hayri Sever Abdulkadir Gorur Mehmet R. Tolun 300-307 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2869&spage=300 2003 conf/iscis/2003 ISCIS db/conf/iscis/iscis2003.html#SeverGT03