1. Department for E-Governance and Administration, Danube University Krems, Krems a. d. Donau, Austria
2. Competence Centre Public IT at Fraunhofer Fokus Berlin, 10589 Berlin, Germany
3. Department OTB – Research for the Built Environment, Faculty of Architecture and the Built Environment, Delft University of Technology, 2628 BL Delft, The Netherlands