Adam Smith, Jean-Baptiste Say, J.R. McCulloch (2013). “History of Economic Theory: The Selected Writings of Adam Smith, Jean-Baptiste Say, and J.R. McCulloch”, p.132, Coventry House Publishing
Samuel Johnson (1787). “The Works of Samuel Johnson, LL.D.: Together with His Life, and Notes on His Lives of the Poets, by Sir John Hawkins, Knt. In Eleven Volumes ...”, p.14