Adam Smith (2007). “The Wealth of Nations: An Inquiry Into the Nature and Causes of the Wealth of Nations: With an introduction by Jonathan B. Wight, University of Richmond”, p.400, Harriman House Limited
Jeremy Taylor (1859). “The Rule and Exercises of Holy Dying: Together with Prayers and Acts of Virtue, and Rules for the Visitation of the Sick, and Offices Proper for that Ministry”, p.11