“…Important issues in algebraic specification refinement, such as the choice of input sorts [36] and the stability of constructors [39,37,10], are automatically resolved in the type-theoretic setting. Other work linking algebraic specification and type theory includes [28,34,2,41,40]. Relevant work using System F and parametricity includes [29,30] showing that the introduction of non-terminating recursion also breaks down the tight correspondence between the existence of a simulation relation and observational equivalence.…”