"P(GA201/03/1161), Z(MSM 272400013)" . . "We show $Sigma^1_1$-completeness of weak bisimilarity for PA (process algebra), and of weak simulation preorder/equivalence for PDA (pushdown automata), PA and PN (Petri nets). We also show $Pi^1_1$-hardness of weak $omega$-trace equivalence for the (sub)classes BPA (basic process algebra) and BPP (basic parallel processes)."@en . . . . "Kluwer Academic Publishers" . "2"^^ . "We show $Sigma^1_1$-completeness of weak bisimilarity for PA (process algebra), and of weak simulation preorder/equivalence for PDA (pushdown automata), PA and PN (Petri nets). We also show $Pi^1_1$-hardness of weak $omega$-trace equivalence for the (sub)classes BPA (basic process algebra) and BPP (basic parallel processes)."@cs . "1"^^ . "14"^^ . "weak bisimilarity;simulation;trace preorder;high undecidability"@en . "RIV/61989100:27240/04:00010317!RIV/2005/GA0/272405/N" . . "[D26B56BF35AC]" . "Highly Undecidable Questions for Process Algebras"@en . "Proc. of 3rd IFIP Intern. Conf. on Theoretical Computer Science (TCS'04)" . "RIV/61989100:27240/04:00010317" . . . "We show $Sigma^1_1$-completeness of weak bisimilarity for PA (process algebra), and of weak simulation preorder/equivalence for PDA (pushdown automata), PA and PN (Petri nets). We also show $Pi^1_1$-hardness of weak $omega$-trace equivalence for the (sub)classes BPA (basic process algebra) and BPP (basic parallel processes)." . "Highly Undecidable Questions for Process Algebras"@cs . . "Jan\u010Dar, Petr" . . "507-520" . . . "1-4020-8156-1" . . . "Dordrecht" . "Highly Undecidable Questions for Process Algebras" . "Highly Undecidable Questions for Process Algebras" . . . "566165" . . "Srba, J." . . "2004-01-01+01:00"^^ . . "27240" . "Toulouse, France" . "Highly Undecidable Questions for Process Algebras"@en . . "Highly Undecidable Questions for Process Algebras"@cs .