- Author: Martin Mike
- Language: English
- Year: 2015
- Author: Döring Dorothea, Ketter Daphne, Schneider Barbara
- Language: German
- Year: 2018
- Author: Hornfischer James D
- Language: English
- Year: 2006
- Author: Hornfischer James D
- Language: English
- Year: 2006
- Author: Cato, Schönberger Otto
- Language: German
- Year: 2011