About.Com-Communism
http://www.history1900s.about.com/homework/history1900s/cs/communism/
Links to information about 20th Century communist movements and the fall of communism.

The Museum of Communism
http://www.gmu.edu/departments/economics/bcaplan/museum/musframe.htm

Frederich Engels-The Principles of Communism
http://www.marxists.org/archive/marx/works/1840/prin-com.htm

World Socialist Movement
http://www.worldsocialism.org/