George Berkeley, Alexander Campbell Fraser (1732). “The Works of George Berkeley, D.D., Formerly Bishop of Cloyne: Philosophical works, 1732-33: Alciphron. The theory of vision”, p.32
George Berkeley (1843). “The Works of George Berkeley: Including His Letters to Thomas Prior, Dean Gervais, Mr. Pope, Etc. : to which is Prefixed an Account of His Life”, p.85