Eugene Charniak Mark Johnson Micha Elsner Joseph Austerweil David Ellis Isaac Haxton Catherine Hill R. Shrivaths Jeremy Moore Michael Pozar Theresa Vu Multilevel Coarse-to-Fine PCFG Parsing. 2006 conf/naacl/2006 HLT-NAACL http://acl.ldc.upenn.edu/N/N06/N06-1022.pdf db/conf/naacl/naacl2006.html#CharniakJEAEHHSMPV06