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
Ben Bernanke's Semiannual Monetary Policy Report to the Congress Before the Committee on Financial Services, U.S. House of Representatives, www.federalreserve.gov. February 15, 2006.