Jean Baptiste Say, Charles Robert Prinsep (1857). “A Treatise on Political Economy; Or, The Production, Distribution, and Consumption of Wealth”, p.487
"A Treatise On Political Economy". Book by Jean-Baptiste Say. Translated from the Fourth Edition of the French by C.R. Prinsep, M.A. With Notes by the Translator. (Sixth American Edition), Chapter VI, p. 323, 1832.