- Author: Paul J.J. Welfens
- Language: German
- Year: 2019
- Author: Paul J.J. Welfens
- Language: English
- Year: 2019
- Author: Jens K. Perret Paul J. J. Welfens
- Language: German
- Year: 2019
- Author: Paul J.J. Welfens
- Language: English
- Year: 2017
- Author: Paul J.J. Welfens (auth.)
- Language: German
- Year: 2017
- Author: Jens K. Perret Paul J. J. Welfens (auth.)
- Language: German
- Year: 2016