Bi-Heyting algebras, toposes and modalities Gonzalo E. ReyesHouman Zolfaghari OriginalPaper Pages: 25 - 43
Discrete tense logic with infinitary inference rules and systematic frame constants: A Hilbert-style axiomatization Lennart Åqvist OriginalPaper Pages: 45 - 100
The shortest possible length of the longest implicational axiom Dolph Ulrich OriginalPaper Pages: 101 - 108