Douglas K. Brown

Vitali's Theorem and WWKL

Stephen G. Simpson, S. G. Simpson, Mariagnese Giusto, 2002, Arch. Math. Log..

Notions of compactness in weak subsystems of second order arithmetic

S. G. Simpson, Douglas K. Brown, 2016 .

Which set existence axioms are needed to prove the separable Hahn-Banach theorem?

S. G. Simpson, Douglas K. BROWN, Stephen G. SIMPSON, 1986, Ann. Pure Appl. Log..

The Baire category theorem in weak subsystems of second-order arithmetic

Stephen G. Simpson, S. G. Simpson, Douglas K. Brown, 1993, Journal of Symbolic Logic.