Howard Barringer Graham Gough Derek Brough Dov M. Gabbay Ian M. Hodkinson Anthony Hunter Richard Owens Peter McBrien Mark Reynolds Michael Fisher Languages, Meta-languages and METATEM, A Discussion Paper. 255-272 1996 4 Logic Journal of the IGPL 2 http://dx.doi.org/10.1093/jigpal/4.2.255 db/journals/igpl/igpl4.html#BarringerGBGHHOMRF96