- Author: Fridtjof Toenniessen
- Language: German
- Year: 2009
- Author: Gerhard Klebe
- Language: German
- Year: 2009
- Author: Thomas Wanhoff
- Language: German
- Year: 2011
- Author: Oliver Hummel
- Language: German
- Year: 2011
- Author: Andreas Filler
- Language: German
- Year: 2011
- Author: George Grätzer
- Language: German
- Year: 2010
- Author: Volker Storch Ulrich Welsch
- Language: German
- Year: 2009
- Author: Martin Kappas
- Language: German
- Year: 2009
- Author: Christine Schütt Barbara Bröker
- Language: German
- Year: 2011