This is pretty well accepted information.
https://www.nytimes.com/2020/07/01/opinion/economic-inequali...
https://www.washingtonpost.com/news/wonk/wp/2018/02/06/how-r...
https://www.nytimes.com/2020/07/01/opinion/economic-inequali...
https://www.washingtonpost.com/news/wonk/wp/2018/02/06/how-r...
Paywall link Paywall link Makes a slight case but mostly just assumes inequality is bad.