- Author: H.A. Walter-London
- Language: English
- Year: 1914
- Author: Hans Wolfgang Singer
- Language: German
- Year: 1912
- Author: Ernst Schultze
- Language: German
- Year: 1912
- Author: Hans E. von Berlepsch-Valendàs
- Language: German
- Year: 1912
- Author: Ernst Leopold Stahl
- Language: German
- Year: 1914
- Author: Ernst Schultze (editor), Ernst Sieper (editor)
- Language: German
- Year: 1912