A Complete Fragment of LTL(EB)

The verification of liveness conditions is an important aspect of state-based rigorous methods. This article investigates this problem in a fragment □LTL of the logic LTL(EB), the integration of the UNTIL-fragment of Pnueli's linear time temporal logic (LTL) and the logic of Event-B, in which the most commonly used liveness conditions can be expressed. For this fragment a sound set of derivation rules is developed, which is also complete under mild restrictions for Event-B machines.