EN
CONTENTS
Introduction..........................................................................5
1. Isomorphism types of linear subsets................................6
2. Countably based types: algebraic results......................11
3. Sets with c.c.c................................................................15
4. Complements in K; closed isomorphism types...............19
5. Covers of 0....................................................................24
6. Atoms, anti-atoms, and join-irreducible types................27
7. The structure of c.c.c. sets............................................34
8. Open questions.............................................................38
Bibliography.......................................................................39