Leivant, Daniel Implicational complexity in intuitionistic arithmetic. (English) Zbl 0488.03032 J. Symb. Log. 46, 240-248 (1981). MSC: 03F50 03F30 PDF BibTeX XML Cite \textit{D. Leivant}, J. Symb. Log. 46, 240--248 (1981; Zbl 0488.03032) Full Text: DOI
Leivant, Daniel On the proof theory of the modal logic for arithmetic provability. (English) Zbl 0464.03019 J. Symb. Log. 46, 531-538 (1981). MSC: 03B45 03F05 PDF BibTeX XML Cite \textit{D. Leivant}, J. Symb. Log. 46, 531--538 (1981; Zbl 0464.03019) Full Text: DOI