Blitzkrieg
Yerxa, Donald (June 2011). "Military History at the Operational Level: An Interview with Robert M. Citino". Historically Speaking. 12 (3): 10–12. doi:10.1353/hsp.2011.0039. S2CID 162320393.

Websites: Andreas, Peter (2020). "How Methamphetamine Became a Key Part of Nazi Military Strategy (January 7, 2020)". Time. Time USA, LLC. Retrieved 23 February 2022.
De Gaulle, Charles (2009). "1890–1940: un officier non-conformiste" [1890–1940: An Unorthodox Officer]. charles-de-gaulle.org (in French). Archived from the original on 25 May 2015. Retrieved 13 December 2009.

Further reading: 

External links: Armstrong, G. P. The Controversy over Tanks in the British Army 1919 to 1933 (PhD 1976)
Sinesi, Michael. Patrick. Modern Bewegungskrieg: German Battle Doctrine, 1920–1940 (2001)
Vardi, Gil-Li. The Enigma of German Operational Theory: the Evolution of Military Thought in Germany, 1919–1938 (PhD 2008)
Spiegel Online: The Nazi Death Machine, Hitler's Drugged Soldiers