1. Which set existence axioms are needed to prove the separable Hahn-Banach theorem?;Brown;Ann. Pure Appl. Logic,1986
2. Weak comparability of well orderings and reverse mathematics;Friedman;Ann. Pure Appl. Logic,1990
3. A finite combinatorial principle which is equivalent to the 1-consistency of predicative analysis;Friedman,1982
4. Real and Complex Analysis;Rudin,1966