1. Eine Verschärfung des Beschränktheitssatzes;Beckmann,1992
2. An optimal boundedness theorem for infinitary logic and its application to descriptive set theory;Beckmann,1996
3. Recursion Theoretic Hierarchies;Hinman,1978
4. Descriptive Set Theory;Moschovakis,1980
5. Proof Theory. An Introduction;Pohlers,1989