Univ. de Paris-Sud, Centre d'Orsay, Laboratoire de Recherche en Informatique, Bat. 490, 91405 Orsay (France), Rapport de Recherche No. 197, December 1984.
Also in: Jouannaud, J.P.: Lecture Notes in Computer Science, Vol. 202: Rewriting Techniques and Applications. Proceedings of the First Int. Conf. on Rewriting Techniques and Applications, 1985, Univ. de Dijon, France, pages 271-286. Berlin, Germany: Springer-Verlag, September 1985.