Marc Moens Jonathan Calder Ewan Klein Mike Reape Henk Zeevat Expressing generalizations in unification-based grammar formalisms. 174-181 1989 conf/eacl/1989 EACL http://acl.ldc.upenn.edu/E/E89/E89-1024.pdf db/conf/eacl/eacl1989.html#MoensCKRZ89