Jean H. Gallier Paliath Narendran David A. Plaisted Stan Raatz Wayne Snyder An Algorithm for Finding Canonical Sets of Ground Rewrite Rules in Polynomial Time. 1-16 1993 40 J. ACM 1 db/journals/jacm/jacm40.html#GallierNPRS93 http://doi.acm.org/10.1145/138027.138032