1. An ordinal analysis of parameter free Π¹₂-comprehension

   • Michael Rathjen

   OriginalPaper 01 September 2004 Pages: 263 - 362

2. Models of set theory with definable ordinals

   • Ali Enayat

   OriginalPaper 01 September 2004 Pages: 363 - 385

3. Diamond, square, and level by level equivalence

   • Arthur W. Apter

   OriginalPaper 09 October 2004 Pages: 387 - 395