the nonsense song
http://www.charliechaplin.com/en/articles/114-Nonsense-Song-from-Modern-Times-Titine-
This link shows a clip and gives an explanation of the nonsense song, as well as some of the lyrics.
Biography of Chaplin
http://www.charliechaplin.com/en/articles/biography
this site offers a lot of good information on Chaplin, including this brief biography
History of the HUAC
https://www.history.com/topics/cold-war/huac
This history of the House Un-American Activities Committee during anti-communist paranoia in the US is useful for understanding the anti-communist accusations against Chaplin
