"How Many Americans Does It Take to Change a Dim Bulb?". L. Neil Smith's remarks to the Second Annual Freedom Summit in Phoenix, Arizona, www.lneilsmith.org. October 12-13, 2002.
Justus von Liebig (1859). “Familiar Letters on Chemistry, in its relation to Physiology, Dietetics, Agriculture, Commerce and Political Economy: Edited by John Blyth”, p.5
Scott Bedbury, Stephen Fenichell (2003). “A New Brand World: Eight Principles for Achieving Brand Leadership in the Twenty-First Century”, p.33, Penguin