http://asianhistory.about.com/od/china/a/TiananmenSquare.htm

http://www.gwu.edu/~nsarchiv/NSAEBB/NSAEBB16/documents/index.html

http://news.bbc.co.uk/onthisday/hi/dates/stories/june/4/newsid_2496000/2496277.stm

http://www.history.com/this-day-in-history/tiananmen-square-massacre-takes-place

http://topics.nytimes.com/topics/news/international/countriesandterritories/china/tiananmen-square/index.html