Thomas E. Woods, Jr., Kevin R. C. Gutzman (2008). “Who Killed the Constitution?: The Fate of American Liberty from World War I to George W. Bush”, p.92, Crown Forum
David Ricardo, John Ramsay McCulloch (1846). “The Works of David Ricardo, Esq., M.P.: With a Notice of the Life and Writings of the Author”, p.31, London, J. Murray