1. Peter Geiger, University of Regensburg, Regensburg, Germany D-93053 or .
2. Marcelo Cajias, University of Regensburg, Regensburg, Germany D-93053 and Patrizia Immobilien AG, Augsburg, Germany D-86150 or .
3. Franz Fuerst, University of Cambridge, Cambridge, United Kingdom CB3 9EP or .