Evgenia Dimitriadou Andreas Weingessel Kurt Hornik A Mixed Ensemble Approach for the Semi-supervised Problem. 571-576 2002 conf/icann/2002 ICANN http://link.springer.de/link/service/series/0558/bibs/2415/24150571.htm db/conf/icann/icann2002.html#DimitriadouWH02