1. “Toposes Without Points”;Barry;J. Pure and Applied Algebra,1974
2. “Sheaves and Logic”;Fourman,1979
3. “Eine Interpretation des Intuitionischen Aussagenkalkuls,”;Gödel;Ergebnisse eines mathmatischen Kolloguiums.,1932
4. “Spistemic Arithmetic is a Conservative Extension of Intuitionistic Arithmetic”;Goodman;Journal of Symbolic Logic,1984
5. Notes on Realizability Toposes;Hyland,1979