Jean Baptiste Say (1821). “A treatise on political economy; or, The production, distribution, and consumption of wealth. Tr. by C.R. Prinsep, with notes”, p.257
Jean Baptiste Say, Charles Robert Prinsep (1857). “A Treatise on Political Economy; Or, The Production, Distribution, and Consumption of Wealth”, p.487
William Poundstone (2010). “Fortune's Formula: The Untold Story of the Scientific Betting System That Beat the Casinos and Wall Street”, p.132, Macmillan