- Author: Wolfgang Blösel Winfried Schmitz Gunnar Seelentag Jan Timmer
- Language: German
- Year: 2014
- Author: Winfried Schmitz
- Language: German
- Year: 2007
- Author: Winfried Schmitz
- Language: German
- Year: 2004
- Author: Winfried Schmitz
- Language: German
- Year: 2004
- Author: Prof. Dr. Winfried Schmitz-Esser (auth.)
- Language: German
- Year: 2000