1. Applications of the proper forcing axiom;Baumgartner,1984
2. The integers and topology;van Douwen,1984
3. There can be C⁎-embedded dense proper subspaces in βω−ω;van Douwen;Proc. Am. Math. Soc.,1989
4. A non-trivial copy of βN∖N;Dow;Proc. Am. Math. Soc.,2014
5. PFA and ω1⁎;Dow,1988