1. Laboratory for High Performance Ceramics, Empa—Swiss Federal Laboratories for Materials Science and Technology, CH-8600 Dübendorf, Switzerland
2. Department of Chemistry, University of Basel, CH-4056 Basel, Switzerland
3. Department of Non-metallic Materials, ETH Zürich, CH-8093 Zürich, Switzerland
4. Institut für Physik, Humboldt-Universität zu Berlin, D-12489 Berlin, Germany
5. Jabatan Fizik, Universiti Pendidikan Sultan Idris, 35900 Perak, Malaysia
6. Department of SciTec, University of Applied Sciences Jena, D-07745 Jena, Germany
7. Laboratory for Photonics and Interfaces, Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne, Switzerland
8. Technische Universität Bergakademie Freiberg, D-09596 Freiberg, Germany