V. Kell Albert Maier Andreas Potthoff Wolfgang Thomas U. Wermuth AMORE: A System for Computing Automata, MOnoidsm and Regular Expressions. 537-538 1989 conf/stacs/1989 STACS db/conf/stacs/stacs89.html#KellMPTW89 http://dx.doi.org/10.1007/BFb0029017