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Krech, Eva-Maria; Stock, Eberhard; Hirschfeld, Ursula; Anders, Lutz Christian (2009). Deutsches Aussprachewörterbuch [German Pronunciation Dictionary] (in German). Berlin: Walter de Gruyter. pp. 913, 951. ISBN978-3-11-018202-6.
"Neuzugänge beim SK Rapid" [New signings at SK Rapid] (in German). SK Rapid Wien. 4 June 2014. Archived from the original on 7 August 2014. Retrieved 22 February 2015.
"Neuzugänge beim SK Rapid" [New signings at SK Rapid] (in German). SK Rapid Wien. 4 June 2014. Archived from the original on 7 August 2014. Retrieved 22 February 2015.