1. The undecidability of k-provability;Buss;Annals of Pure and Applied Logic,1991
2. Interpolants, cut elimination and flow graphs for the propositional calculus;Carbone;Annals of Pure and Applied Logic,1997
3. Duplication of directed graphs and exponential blow up of proofs;Carbone;Annals of Pure and Applied Logic,1999
4. Streams and strings of formal proofs;Carbone;Theoretical Computer Science,2002
5. A graphic apology for symmetry and implicitness;Carbone,2000