Personal Communications>Interview:  Obama, Barack (27 December 2017), Prince Harry interviews Barack Obama, BBC, Retrieved on 2018-01-06

Source Material [www.bbc.co.uk]

Books, Brochures, and Chapters>Book:  Ridley , Matt (2010), The Rational Optimist: How Prosperity Evolves, Retrieved on 2017-09-22

Electronic/World Wide Web>Internet Article:  Pinker, Steven (12/6/2016), The United States is Not an Apocalyptic Wasteland, Explains Steven Pinker, Retrieved on 2016-12-29

Source Material [www.3quarksdaily.com]

Electronic/World Wide Web>Internet Article:  Brand, Stewart and Dyson , Freeman (02.01.98), Freeman Dyson's Brain, Wired, Retrieved on 2016-06-22

Source Material [www.wired.com]