1. The theory of countable analytical sets;Kechris, Alexander S.;Trans. Amer. Math. Soc.,1975
2. On projective ordinals;Kechris, Alexander S.;J. Symbolic Logic,1974
3. A theorem on hyperhypersimple sets;Martin, Donald A.;J. Symbolic Logic,1963
4. A basis theorem for ∑₃¹ sets of reals;Martin, D. A.;Ann. of Math. (2),1969
5. 5. D. A. Martin and R. M. Solovay, Basis theorems for ∑¹₃ sets of reals (to appear).