1. “Recursive isomorphism” and effectively extensible theories;Boykan Pour-El;Bull. Amer. Math. Soc.,1965
2. Combinatorial Functors;Crossely,1974
3. Computability and Unsolvability;Davis,1958
4. A non-constructive extension of the number system, two abstracts;Dekker;J. Symbolic Logic,1955
5. Isols and the pigeonhole principle;Dekker;J. Symbolic Logic,1989