Alexander Pope (1763). “An essay on man: By Alexander Pope, Esq. Enlarged and improved by the author. Together with his MS. additions and variations as in the last edition of his works. With the notes of William, Lord Bishop of Gloucester”, p.70
Henry David Thoreau (2014). “Citizen Thoreau: Walden, Civil Disobedience, Life Without Principle, Slavery in Massachusetts, A Plea for Captain John Brown”, p.152, Graphic Arts Books