Quasi continuous selections of upper Baire continuous mappings

Milan Matejdes

The paper deals with the existence problem of selections for a closed valued and $c$-upper Baire continuous multifunction $F$. The main goal is to find a minimal $usco$ multifunction intersecting $F$ and its selection that is quasi continuous everywhere except at points of a nowhere dense set. The methods are based on properties of minimal multifunctions and a cluster multifunction generated by a cluster process with respect to the system of all sets of second category with the Baire property.