CTL model checking for labelled tree queries

Querying and efficiently validating properties on labelled tree structures has become an important part of research in numerous domains. In this paper we show how a fragment of XPath called Configuration Logic (CL) can be embedded into Computation Tree Logic. This framework embeds into CTL a larger subset of XPath than previous work and in. particular allows universally and existentially quantified variables in formulas. Finally, we show how the variable binding mechanism of CL can be seen as a branching-time equivalent of the "freeze" quantifier.