Zur Stetigkeit in kompakten projektiven Ebenen. (About continuity in compact projective planes) (Q919274)

A projective plane (P,\({\mathfrak L})\) is a topological plane in the sense of Lenz if P and \({\mathfrak L}\) are topological spaces such that all maps (x\(\to px): P\setminus \{p\}\to {\mathfrak L}\) and their duals are continuous. If, moreover, P and \({\mathfrak L}\) are compact, then joining and intersection are continuous in both variables.