The legacy of Professor Jan Stanisław Lipiński for the sake of the development of mathematics in Gdańsk 1969-1998 Convergence of sequences of measurable functions In uniform convergence and some related types of convergence Points of quasicontinuity and of similar generalizations of continuity Topological and algebraic aspects of subsums of series In the abstract density topologies generated by lower and almost lower density operators. ukryj opis