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- Language: German
- Year: 2013
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- Language: German
- Year: 2013
- Author: Der Aktionär 46 2013
- Language: German
- Year: 2013
- Author: Wirtschafts Woche 46 2013
- Language: German
- Year: 2013
- Author: FinanzTest 09 2013
- Language: German
- Year: 2013
- Author: Finanztest 11 2013
- Language: German
- Year: 2013
- Author: Börse Online Magazin - No 40 2013
- Language: German
- Year: 2013
- Author: Wirtschaftswoche 39 2013
- Language: German
- Year: 2013
- Author: Finanztest 10 2013
- Language: German
- Year: 2013
- Author: Der Aktionär 40 2013 25.09.2013
- Language: German
- Year: 2013