http://citeseer.ist.psu.edu/dellapietra95inducing.html http://www-2.cs.cmu.edu/afs/cs/user/aberger/www/html/tutorial/tutorial.html http://www.cs.rutgers.edu/~vladimir/pub/choudhury02icpr.pdf http://www.cs.huji.ac.il/~nirf/Abstracts/FrGG1.html http://citeseer.ist.psu.edu/mccallum00maximum.html http://www.cs.ucsd.edu/users/elkan/254spring02/gidofalvi.pdf http://citeseer.ist.psu.edu/lafferty01conditional.html