As dificuldades económicas dos anos 30

http://www.navegar.com.pt/navegar2_quiz/historia/anos30/index.html

http://www.deemo.com.pt/exercicios/hist/9/10.1dea30.htm

http://www.malhatlantica.pt/sitiodahistoria/FichasTema10.htm

http://historiajulia-exercicios.blogspot.com/2007/11/crise-de-1929-e-o-nazi-fascismo.html