L. Soukup
Building on a method of U. Abraham and S. Todorcevic we prove a preservation theorem on certain properties under c.c.c forcings. Applying this result we show that (1) an uncountable, first countable, 0-dimensional space containing only countable and co-countable open subspaces, and (2) S- and L-groups can exist under Martin's Axiom.
Key words and phrases: Martin's Axiom, S-space, L-space, S-group, L-group, first countable, Ostaszewsky-space, preservation, iterated forcing
1991 Mathematics Subject Classification: 03E35, 54E25