https://en.wikipedia.org/wiki/Soviet_Union
https://en.wikipedia.org/wiki/Nikita_Khrushchev
https://en.wikipedia.org/wiki/Democratic_centralism
https://en.wikipedia.org/wiki/Five-year_plans_of_the_Soviet_Union
https://www.history.com/topics/russia/history-of-the-soviet-union
https://ehistory.osu.edu/exhibitions/russian_revolution/WorldWar_and_Intl_Rev
https://en.wikipedia.org/wiki/Death_and_state_funeral_of_Joseph_Stalin