1. “Eine Interpretation des intuitionistischen Aussagenkalküls.”;GÖDEL;Ergebnisse eines mathematischen Kolloquiums,1933
2. “Some relational systems and the associated topological spaces.”;GRZEGORCZYK;Fundamenta mathematical,1967
3. 'Solution of a problem of Leon Henkin',;LÖB;The journal of symbolic logic,1955
4. “Some theorems about the sentential calculi of Lewis and Heyting.”;MCKINSEY;The journal of symbolic logic,1948