Drahomíra "johanka" Spoustová Jan Hajic Jan Raab Miroslav Spousta Semi-Supervised Training for the Averaged Perceptron POS Tagger. 763-771 2009 EACL http://www.aclweb.org/anthology/E09-1087 conf/eacl/2009 db/conf/eacl/eacl2009.html#SpoustovaHRS09