http://www.theatlantic.com/business/archive/2015/07/america-...
http://www.economist.com/news/united-states/21595437-america...
https://www.brookings.edu/blog/social-mobility-memos/2015/05...
http://www.epi.org/publication/usa-lags-peer-countries-mobil...
http://www.economist.com/news/briefing/21640316-children-ric...
https://www.washingtonpost.com/news/wonk/wp/2016/08/03/there...
http://www.theatlantic.com/business/archive/2015/07/america-...
http://www.economist.com/news/united-states/21595437-america...
https://www.brookings.edu/blog/social-mobility-memos/2015/05...
http://www.epi.org/publication/usa-lags-peer-countries-mobil...
http://www.economist.com/news/briefing/21640316-children-ric...
https://www.washingtonpost.com/news/wonk/wp/2016/08/03/there...