1. A note on admissible ordinals;Friedman,1968
2. Omitting types; applications to recursion theory;Grilliot;J. Symbolic Logic,1972
3. The Model Theory of Infinitary Languages;Keisler,1971
4. Forcing with perfect closed sets;Sacks,1971
5. Degrees of Unsolvability;Sacks,1963-1966