1. A.J.I. Jones (1983). Communication and meaning: An essay in appplied modal logic. Synthese Library. Reidel.
2. Chellas, B. F. (1988). Modal Logic: An introduction. Cambridge University Press.
3. Cohen, P. and Levesque, H. (1990). Rational interaction as the basis for communication. In Cohen, P., Morgan, J., and Pollack, M., editors, Intentions in Communications. The MIT Press.
4. Cohen, P. R. and Perrault, C. R. (1979). Elements of a Plan-Based Theory of Speech Acts. Cognitive Science, 1: 177–212.
5. Demolombe, R. (1996). Validity Queries and Completeness Queries. In Proc. of 9th International Symposium on Methodologies for Intelligent Systems.