Tài liệu tham khảo WikiPedia: Pythagora Switch http://www.nhk.or.jp/jp-prize/english/2003/jyusyou... http://www.nhk.or.jp/kids/program/pitagora.html http://www3.nhk.or.jp/pr/english/press/pdf/2004062... https://www.imdb.com/title/tt0991057/
