The cluster set structure of Darboux Baire 1 functions
In this paper the author characterizes the cluster set structure of Darboux Baire 1 functions. This characterization is formulated in terms of conditions on subsets of the plane, \(R^ 2\), and involves the upper and lower envelopes of the sets. These conditions are necessary and sufficient for a set in \(R^ 2\) to form the cluster set structure of a Darboux Baire 1 function.
scientific article; zbMATH DE number 3871694