1. Chair for International Economics; Ruhr University of Bochum; Bochum Germany
2. Chair for Macroeconomics; University of Duisburg-Essen; Essen Germany
3. Kiel Institute for the World Economy; Kiel Germany
4. Chair for Applied Statistics and Empirical Economics; University of Bremen; Bremen Germany
5. Chair for Empirical Economics; Chemnitz University of Technology; Chemnitz Germany
6. FOM Hochschule für Oekonomie & Management; University of Applied Sciences; Essen Germany