1. Natural Deduction; the Logical Basis of Axiom Systems;ANDERSON,1962
2. Remarks on Intuitionistic Logic.;BETH,1959
3. On the Definition of Substitution, Replacement and Allied Notions in an Abstract Formal System;CURRY;Rev. Philos. Louvain,1952
4. Foundations of Mathematical Logic;CURRY,1963
5. The Inferential Approach to Logical Calculus;CURRY;Logique et Analyse,1960