- Author: Trygve Wyller
- Language: German
- Year: 2009
- Author: Trygve Wyller, Daria Pezzoli-Olgiati, Stefanie Knauss, Hans-Günter Heimbrock, Hans-Joachim Sander, Carla Danani
- Language: English
- Year: 2019
- Author: Jose Casanova, Rosemarie van den Breemer, Trygve Wyller
- Language: English
- Year: 2013
- Author: Usha S. Nayar, Trygve Wyller
- Language: English
- Year: 2007