Alberto Momigliano Simon Ambler Roy L. Crole A Hybrid Encoding of Howe's Method for Establishing Congruence of Bisimilarity. 2002 70 Electr. Notes Theor. Comput. Sci. 2 http://www.elsevier.com/gej-ng/31/29/23/125/50/show/Products/notes/index.htt#006 db/journals/entcs/entcs70.html#MomiglianoAC02