- Author: Wiese Marion
- Language: German
- Year: 2006
- Author: Walter Helge
- Language: German
- Year: 1996
- Author: Wadle Elmar
- Language: German
- Year: 1993
- Author: Wadle Elmar
- Language: German
- Year: 2001
- Author: Schrage Eltjo J. H.
- Language: German
- Year: 1992
- Author: Tießler-Marenda Elke
- Language: German
- Year: 2002
- Author: Theewen Eckhard M.
- Language: German
- Year: 1991
- Author: Seynsche Gudrun
- Language: German
- Year: 2003