Funding for this research was provided by:
Volkswagen Foundation (Lichtenberg Professorship)
Air Force Office of Scientific Research (FA9550-14-1-0095)
Deutsche Forschungsgemeinschaft (BA816/15-4, MO1408/1-2, GRK1885, HE6221/1-1)
Article History
Received: 9 December 2016
Revised: 6 March 2017
Accepted: 7 March 2017
First Online: 1 April 2017