PPT Slide
The ideas and methods are taken from:
formulas en definitions: Epistemic Logic for AI and Computer Science: J.-J.Ch. Meyer and W. van der Hoek, 1995
extensive description of the problem: Reasoning About Knowledge: R. Fagin, J.Y. Halpern, Y.Moses, M.Y. Vardi, 1995
confirmations as a non-simultaneous run: Common Knowledge and Update in Finite Environments: Ron van der Meyden, 1997