Hannah Schwär, «Puma and Adidas’ Rivalry Has Divided a Small German Town for 70 Years — Here’s What It Looks Like Now», Business Insider Deutschland, October 1, 2018; Ellen Emmerentze Jervell, «Where Puma and Adidas Were Like Hatfields and McCoys», Wall Street Journal, December 30, 2014, ; Allan Hall, «Adidas and Puma Bury the Hatchet after 60 Years of Brothers’ Feud after Football Match», Daily Telegraph, September 22, 2009, .
