Einsiedler, Martin (14 August 2010). "Herthas erste Pflicht ist erfüllt" (in German). Der Tagesspiegel. Archived from the original on 17 August 2010. Retrieved 9 December 2012.
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Einsiedler, Martin (14 August 2010). "Herthas erste Pflicht ist erfüllt" (in German). Der Tagesspiegel. Archived from the original on 17 August 2010. Retrieved 9 December 2012.
"Otto, pass auf!" [Otto, watch out!] (in German). DFL. 4 March 2012. Archived from the original on 15 June 2012. Retrieved 3 September 2012.