Affiliation: | 1.Ruhr-Universit?t Bochum, Fakult?t für Mathematik, 44780 Bochum, Germany (e-mail: holger.dette@ruhr-uni-bochum.de),DE;2.WestLB, Department: 001-61600, Friedrichstrasse 62-80, 40217 Düsseldorf, Germany (e-mail: carsten_von_lieres@WestLB.de),DE |