1. Anderson, A. R., & Belnap, N. D. Jr. (1975). Entailment (Vol. 1). Princeton, NJ: Princeton University Press.
2. Barendregt, H. P. (1984). The lambda calculus, its syntax and semantics. North Holland.
3. Davies, R., & Pfenning, F. (2001). A modal analysis of staged computation. Journal of the ACM, 48(3), 555–604.
4. Dummett, M. (1991). The logical basis of metaphysics. Cambridge, MA: Harvard University Press.
5. Dyckhoff, R. (1987). Implementing a simple proof assistant. In Proceedings of the workshop on programming for logic teaching. Leeds Centre for Theoretical Computer Science Proceedings 23.88, 1988., Leeds, July.