Between ${\cal A}$- and ${\cal B}$-sets

2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/77642The aim of this paper is to introduce the class of ${\cal A}{\cal B}$-sets as the sets that are the intersection of an open and a semi-regular set. Several classes of well-known topological spaces are characterized via the new concept. A new decomposition of continuity is provided.to appear in "Mathematica Balkanica"General Topology54G05; 54H05; 54C05; 54C08; 54G99Between ${\cal A}$- and ${\cal B}$-setstext