"Chris O'Dowd on the Genius of Christopher Guest, Working with James Franco, and Grafting". Interview with Scott Raab, www.esquire.com. April 17, 2014.
Andrew Dickson White (2012). “A History of the Warfare of Science with Theology in Christendom: From Creation to the Victory of Scientific and Literary Methods”, p.52, Transaction Publishers
"Principles of political economy considered with a view to their practical application". Book by Thomas Robert Malthus, Book II, Chapter I, "On The Progress of Wealth", Section X, p. 430, 1836.