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- Language: German
- Year: 2015
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- Language: German
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- Year: 2014
- Author: Frisch Shelley Laura, Klein Stefan
- Language: English, German
- Year: 2011
- Author: Bernhard Keller Hans-Werner Klein Stefan Tuschl
- Language: German
- Year: 2019
- Author: Klein Stefan
- Language: German
- Year: 2014