1. University of Applied Sciences Niederrhein Faculty of Chemistry, Chemical Engineering Adlerstraße 32 47798 Krefeld Germany
2. LANXESS Deutschland GmbH Business Unit Inorganic Pigments Kennedyplatz 1 50569 Köln Germany
3. University of Duisburg-Essen Faculty of Chemistry Universitätsstraße 7 45141 Essen Germany