Northrop Frye, Robert D. Denham (2003). “Northrop Frye's Notebooks and Lectures on the Bible and Other Religious Texts”, p.158, University of Toronto Press
Mark Twain (2014). “Mark Twain on Common Sense: Timeless Advice and Words of Wisdom from America's Most-Revered Humorist”, p.32, Skyhorse Publishing, Inc.