Stefano Melacci Marco Maggini Marco Gori Semi-supervised Learning with Constraints for Multi-view Object Recognition. 653-662 2009 ICANN (2) http://dx.doi.org/10.1007/978-3-642-04277-5_66 conf/icann/2009-2 db/conf/icann/icann2009-2.html#MelacciMG09