Fayin Li Harry Wechsler Open World Face Recognition with Credibility and Confidence Measures. 462-469 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2688&spage=462 2003 conf/avbpa/2003 AVBPA db/conf/avbpa/avbpa2003.html#LiW03