1. Disjoint refinement;Balcar,1989
2. Measure and category-filters on ω;Bartoszynski,1992
3. Structural properties of ideals;Baumgartner;Dissertationes Mathematicae,1982
4. Selective ultrafilters and homogeneity;Blass;Ann. Pure Appl. Logic,1988
5. Groupwise density and related cardinals;Blass;Arch. Math. Logic,1990