- Author: Gerhard Grethlein
- Language: German
- Year: 1961
- Author: Gerhard Grethlein
- Language: German
- Year: 1959
- Author: Rudolf Brunner (editor), Gerhard Grethlein (editor)
- Language: German
- Year: 1975
- Author: Gerhard Grethlein, Rudolf Brunner
- Language: German
- Year: 1969
- Author: Gerhard Grethlein
- Language: German
- Year: 1966
- Author: Gerhard Grethlein
- Language: German
- Year: 1965