Say 1821, p. 5Say, Jean-Baptiste (1821). Letters to Mr. Malthus. London: Sherwood, Neely, and Jones. This is an English translation of Say's Lettres à M. Malthus sur l'économie politique et la stagnation du commerce, published in 1820.
Foley, Duncan (2008). Adam's Fallacy: A Guide to Economic Theology. Harvard University Press. p. 184.
Cowen, Tyler (2000). "Say's Law and Keynesian Economics". In Wood, John Cunningham; Kates, Steven (eds.). Jean-Baptiste Say: Critical Assessments of Leading Economists. Vol. V. London: Routledge. p. 305.
Thweatt, William O. (2000). "Early Formulators of Say's Law". In Wood, John Cunningham; Kates, Steven (eds.). Jean-Baptiste Say: Critical Assessments of Leading Economists. Vol. V. London: Routledge. pp. 78–93.
Braudel, The Wheels of Commerce: Civilisation and Capitalism 15th–18th Century, 1979:181
James Mill, Commerce Defended (1808), Chapter VI: "Consumption", p. 81
Malthus, Thomas (1820). Principles of Political Economy Considered With a View to Their Practical Application. London: John Murray. pp. 333–334.