Author(s):  | 
                                    A. J. Dietrich, Institute of Business Administration, University of Hohenheim, Stuttgart, Germany  W. Hümmer, Chair for Database Systems, Friedrich-Alexander-University of Erlangen- Nuremberg, Erlangen, Germany  C. Meiler, Chair for Database Systems, Friedrich-Alexander-University of Erlangen- Nuremberg, Erlangen, Germany  |