- Author: Rolf C. Franck, Madeleine Franck
- Language: German
- Year: 2021
- Author: Franck Madeleine, Franck Rolf C
- Language: German
- Year: 2011
- Author: Franck Rolf C, Franck Madeleine
- Language: German
- Year: 2011
- Author: Franck Madeleine, Franck Rolf C
- Language: German
- Year: 2011