References and Sources

 https://en.wikipedia.org/wiki/Tanks_in_World_War_I
https://en.wikipedia.org/wiki/Tanks_in_World_War_II
https://en.wikipedia.org/wiki/Christie_suspension
https://www.youtube.com/watch?v=bn4uRvgIEJY The First Tank Battle
https://www.youtube.com/watch?v=HykbGm0U2uw Battle of Kursk