Jean Baptiste Say, Charles Robert Prinsep (1857). “A Treatise on Political Economy; Or, The Production, Distribution, and Consumption of Wealth”, p.389
Thomas Jefferson, Henry Augustine Washington (1854). “The Writings of Thomas Jefferson: Being His Autobiography, Correspondence, Reports, Messages, Addresses, and Other Writings, Official and Private : Published by the Order of the Joint Committee of Congress on the Library, from the Original Manuscripts, Deposited in the Department of State”, p.349