https://cn.nytimes.com/obits/20190826/sidney-rittenberg-dead/zh-hant/
https://www.youtube.com/watch?v=F9mfOSP2loU
https://www.youtube.com/watch?v=N1AW4AVZ1pc
https://en.wikipedia.org/wiki/Sidney_Rittenberg
https://civics.sites.unc.edu/files/2014/02/AmericanChina9.pdf