- Author: Frank Bongers, Maximilian Vollendorf
- Language: German
- Year: 2010
- Author: Frank Bongers Maximilian Vollendorf
- Language: German
- Year: 2010
- Author: Frank Bongers
- Language: German
- Year: 2007
- Author: Frank Bongers Andreas Stöckl
- Language: German
- Year: 2010