https://www.worldatlas.com/articles/10-reasons-why-hitler-lost-wwii.html

https://www.history.com/news/how-did-the-nazis-really-lose-world-war-ii

https://www.theguardian.com/world/2009/sep/08/hitler-germany-campaign-collapsed

https://www.richardjevans.com/lectures/germany-lose-second-world-war/

https://www.history.co.uk/article/operation-barbarossa-hitler%25E2%2580%2599s-failed-invasion-of-the-soviet-union

https://www.popularmechanics.com/military/g2652/most-important-battles-world-war-ii/