Abstract Regular Null-Null-Additive Set Multifunctions in Hausdorff Topology

Abstract

Abstract In this paper we introduce and study various types of abstract regularity in Hausdorff topology for monotone set multifunctions, with direct applications in wellknown situations such as the Borel σ-algebra of a Hausdorff space and/or the Borel (Baire, respectively) σ-ring or σ-ring of a locally compact Hausdorff space. Some relationships among abstract regularities are investigated.