We define an equivalence relation on recursive specifications in process algebra that is model-independent and does not involve an explicit notion of solution. Then we extend this equivalence to the specification language $mu$CRL.

Software/Program Verification (acm D.2.4), Formal Definitions and Theory (acm D.3.1), Language Constructs and Features (acm D.3.3), Semantics of Programming Languages (acm F.3.2), Expressions and Their Representation (acm I.1.1)
Modes of computation (nondeterministic, parallel, interactive, probabilistic, etc.) (msc 68Q10), Abstract data types; algebraic specification (msc 68Q65), Models and methods for concurrent and distributed computing (process algebras, bisimulation, transition nets, etc.) (msc 68Q85)
CWI
Software Engineering [SEN]
Specification and Analysis of Embedded Systems

van der Poorten, A.J, & Usenko, Y.S. (2001). Equivalence of recursive specifications in process algebra. Software Engineering [SEN]. CWI.