- Author: Ronald Herbert Sack
- Language: English
- Year: 1972
- Author: Monika Hörig
- Language: German
- Year: 1979
- Author: Monika Hörig
- Language: German
- Year: 1979
- Author: Karl Hecker
- Language: German
- Year: 1974
- Author: Oswald Loretz Werner R. Mayer
- Language: German
- Year: 1978
- Author: Karl Hecker
- Language: German
- Year: 1974
- Author: Volkert Haas Gernot Wilhelm
- Language: German
- Year: 1974