http://www.youtube.com/watch?v=yFjHz_xqEco

http://www.youtube.com/user/tiagomenta?v=NYmyPyCSm5U-assista&lr=1

http://www.brasilescola.com/historiag/democracia-ateniense.htm

http://www.youtube.com/watch?v=AdkgZdz-TJQ