1. Aczel, P. H. G. (1980). Frege structures and the notions of proposition, truth and set. in J. Barwise, H.-J. Keisler, & K. Kunen (Eds.), The Kleene Symposium, Vol. 101 of Studies in logic and the foundations of mathematics (pp. 31–59). Amsterdam: North-Holland Publishing Co. (xx+425pp, 1980. Proceedings of the Symposium held in June 18–24).
2. Aczel, P. H. G. (1991). Term declaration logic and generalised composita. In Sixth Annual IEEE Symposium on Logic in Computer Science ( LICS’91) (pp. 22–30). Amsterdam: IEEE Press. Proceedings of the Symposium held July 15–18, in Amsterdam, The Netherlands.
3. Barendregt, H.P. (1984). The lambda calculus, its syntax and semantics, volume 103 of studies in logic and the foundation of mathematics. Amsterdam: North-Holland (revised edition).
4. Bishop, E. (1967). Foundations of constructive analysis. McGraw-Hill series in Higher Mathematics (xiv+371pp). New York: McGraw-Hill Book Company.
5. Chenadec, Ph. Le. (1989). On the logic of unification. Journal of Symbolic Computation, 8(1 and 2), 141–199.