- Author: Gustav Gröber, Frank-Rutger Hausmann, Frank-Rutger Hausmann
- Language: German
- Year: 2018
- Author: Gustav Gröber, Frank-Rutger Hausmann, Frank-Rutger Hausmann
- Language: German
- Year: 2018
- Author: Hugo Schuchardt (editor), Gustav Gröber (editor)
- Language: German
- Year: 1906