- Author: Richard Hammer
- Language: German
- Year: 2015
- Author: Richard Hammer
- Language: German
- Year: 1998
- Author: Richard Hammer
- Language: German
- Year: 2011
- Author: Richard Hammer
- Language: English
- Year: 2016
- Author: Richard Hammer
- Language: English
- Year: 2017
- Author: Richard Hammer
- Language: English
- Year: 2018