1. Completeness in the theory of types;Henkin;The journal of symbolic logic,1950
2. Algebraic semantics for modal logics;Lemmon;The journal of symbolic logic,1966
3. Boolean algebras with operators;Jónsson;American journal of mathematics,1951
4. Review of [2];Kripke;Mathematical reviews,1967
5. Ideale in vollständigen Mengenkörpern;Tarski;Fundamenta mathematicae,1939