- Author: Sir Ivor W. Jennings Gerhard A. Ritter (auth.)
- Language: German
- Year: 1958
- Author: Joseph N. Wilson Gerhard X. Ritter
- Language: English
- Year: 2000
- Author: Joseph N. Wilson Gerhard X. Ritter
- Language: English
- Year: 2000
- Author: Vassilis G. Kaburlasos Gerhard X. Ritter
- Language: English
- Year: 2007
- Author: Joseph N. Wilson Gerhard X. Ritter
- Language: English
- Year: 2001
- Author: Gerhard X. Ritter Joseph N. Wilson
- Language: English
- Year: 1996
- Author: Joseph N. Wilson Gerhard X. Ritter
- Language: English
- Year: 2000