First Author:   Joerg Lingens University of Regensburg Joerg.Lingens@wiwi.uni-regensburg.de   c/o Prof. Dr. Jürgen Jerger, University of Regensburg, Universitaetsstr. 31 Regensburg, 93051, Germany   ++943 943 2722(Phone) ++943 943 2722(Fax)