by Petr Jančar, Antonín Kučera, These results will be presented at INFINITY`97 workshop. May 1997, 19 pages.
FIMU-RS-97-02. Available as Postscript, PDF.
We describe a general method for deciding bisimilarity for pairs of processes where one process has finitely many states. We apply this method to pushdown processes and to PA processes. We also demonstrate that the mentioned problem is undecidable for `state-extended` PA processes.