The internal and external aspect of logic and set theory in elementary topoi Gerhard Osius (1974) Cahiers de Topologie et Géométrie Différentielle Catégoriques
The lattices of numerations of theories containing Peano's arithmetic Stanislav Palúch (1973) Commentationes Mathematicae Universitatis Carolinae
The observational predicate calculus and complexity of computations (Preliminary communication) Pavel Pudlák (1975) Commentationes Mathematicae Universitatis Carolinae