Countably metacompact spaces in the constructible universe
Tom 143 / 1993
Fundamenta Mathematicae 143 (1993), 221-230 DOI: 10.4064/fm-143-3-221-230
We present a construction from ♢* of a first countable, regular, countably metacompact space with a closed discrete subspace that is not a $G_δ$. In addition some nonperfect spaces with σ-disjoint bases are constructed.