Sources
http://www.coldwar.org/articles/60s/CzechoslovakiaUprising.asp
https://history.state.gov/milestones/1961-1968/soviet-invasion-czechoslavkia
http://www.history.com/topics/cold-war/nikita-sergeyevich-khrushchev
http://www.bbc.co.uk/schools/gcsebitesize/history/mwh/ir2/hungaryrev1.shtml
http://history1900s.about.com/od/people/p/gorbachev.htm
http://www.pbs.org/wgbh/amex/china/peopleevents/pande06.html
https://history.state.gov/milestones/1945-1952/marshall-plan
http://www.ourdocuments.gov/doc.php?flash=true&doc=82
https://history.state.gov/milestones/1945-1952/truman-doctrine
http://www.ushistory.org/us/52c.asp
http://www.britannica.com/EBchecked/topic/294419/Iron-Curtain
http://www.questbg.com/lifestyle/life/676-everyday-life-behind-the-iron-curtain.html
http://www.historyextra.com/feature/culture/pictures-life-behind-iron-curtain
http://www.ironcurtainkid.com/
http://www.spiritoffreedom.org/airlift.html
http://www.history.com/topics/cold-war/berlin-airlift
http://www.history.com/this-day-in-history/the-warsaw-pact-is-formed
http://www.history.com/topics/cold-war/formation-of-nato-and-warsaw-pact
http://www.vocabulary.com/dictionary/brinkmanship
https://history.state.gov/milestones/1961-1968/soviet-invasion-czechoslavkia
http://www.history.com/topics/cold-war/nikita-sergeyevich-khrushchev
http://www.bbc.co.uk/schools/gcsebitesize/history/mwh/ir2/hungaryrev1.shtml
http://history1900s.about.com/od/people/p/gorbachev.htm
http://www.pbs.org/wgbh/amex/china/peopleevents/pande06.html
https://history.state.gov/milestones/1945-1952/marshall-plan
http://www.ourdocuments.gov/doc.php?flash=true&doc=82
https://history.state.gov/milestones/1945-1952/truman-doctrine
http://www.ushistory.org/us/52c.asp
http://www.britannica.com/EBchecked/topic/294419/Iron-Curtain
http://www.questbg.com/lifestyle/life/676-everyday-life-behind-the-iron-curtain.html
http://www.historyextra.com/feature/culture/pictures-life-behind-iron-curtain
http://www.ironcurtainkid.com/
http://www.spiritoffreedom.org/airlift.html
http://www.history.com/topics/cold-war/berlin-airlift
http://www.history.com/this-day-in-history/the-warsaw-pact-is-formed
http://www.history.com/topics/cold-war/formation-of-nato-and-warsaw-pact
http://www.vocabulary.com/dictionary/brinkmanship