1. Beiträge zum Entscheidungsproblem der mathematischen Logik;Ackermann;Math. Annalen,1936
2. P. Bernays and A. Fraenkel, Axiomatic Set Theory. (Amsterdam 1958).
3. A Reduction Class with a Single Dyadic Predicate;Denton;Notices AMS,1963
4. A False Decision Procedure for the Halting Problem;Denton;Notices AMS,1963
5. Classification of AEA Formulas by Letter Atoms;Dreben;Bulletin AMS,1962