1. P. Blackburn and W. Meyer-Viol. Linguistic, logic and finite trees. Bulletin of the IGPL, 2:2–29, 1994.
2. Lecture Notes in Computer Science;P. Blackburn,1996
3. M. J. Fisher and R. F. Ladner. Prepositional dynamic logic of regular programs. Journal of Computer and System Sciences, 18, 1979.
4. CSLI Lecture Notes;R. Goldblatt,1992
5. H. Sahlqvist. Completeness and correspondence in first and second-order semantics for modal logic. In S. Kanger, editor, Proceedings of the third Scandinavian Logic Symposium. North-Holland, Amsterdam, 1975.