- Author: Gerhard Moroff Kai Focke (auth.)
- Language: German
- Year: 2017
- Author: Gerhard Moroff Kai Focke (auth.)
- Language: German
- Year: 2016
- Author: Gerhard Moroff Kai Focke (auth.)
- Language: German
- Year: 2015
- Author: Gerhard Moroff Kai Focke (auth.)
- Language: German
- Year: 2011