**Author details**

Rudolf Zetik, Honghui Yan, Elke Malz, Snezhana Jovanoska, Guowei Shen and Reiner S. Thomä *Ilmenau University of Technology, Germany*

Rahmi Salman, Thorsten Schultze, Robert Tobera and Hans-Ingolf Willms *University Essen-Duisburg, Germany*

Lars Reichardt, Malgorzata Janson, Thomas Zwick and Werner Wiesbeck *Karlsruhe Institute of Technology (KIT), Germany*

Tobias Deißler and Jörn Thielecke *Friedrich-Alexander University Erlangen-Nürnberg, Germany*
