Institution: | a Institute of Mathematics, University of Vienna, Strudlhofgasse 4, A-1090, Vienna, Austria b Institute of Financial and Actuarial Mathematics, Technical University of Vienna, Wiedner Hauptstrasse 8-10, A-1040, Vienna, Austria c Department of Mathematics, West University of Timisoara, Bd. V. Parvan 4, 1900, Timisoara, Romania |