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deadrhetoric.com
McGinn, Kyle (7 August 2016). "Deadlock – On Perseverance". deadrhetoric.com. Archived from the original on 15 August 2016. Retrieved 14 July 2017.
Seitz, Manuela (25 April 2011). "Deadlock im Interview (April 2011)". www.the-pit.de (in German). Munich, Germany. p. 3. Archived from the original on 14 July 2017. Retrieved 14 July 2017.