1. Faculty of Physics, Ludwig-Maximilians-Universität München, Munich, Germany
2. ELAN Institute for Teacher Training, University of Twente, Enschede, The Netherlands
3. Research Centre for Science and Mathematics Education, Autonomous University of Barcelona, Barcelona, Spain
4. Dipartimento di Chimica, Fisica e Ambiente, University of Udine, Udine, Italy
5. Institute of Experimental Physics, University of Wroclaw, Wroclaw, Poland
6. Faculty of Science/Physics Section, Institute of Teacher Education, Université de Genève, Genève, Switzerland
7. Division of Physics Education Research, Department of Physics and Astronomy, Uppsala Universitet, Uppsala, Sweden
8. Department of Materials Physics, Eötvös Loránd University, Budapest, Hungary