Mark Twain (2014). “Mark Twain on Common Sense: Timeless Advice and Words of Wisdom from America's Most-Revered Humorist”, p.30, Skyhorse Publishing, Inc.
"Meatonomics: How the Rigged Economics of Meat and Dairy Make You Consume Too Much–and How to Eat Better, Live Longer, and Spend Smarter". Book by David Robinson Simon, September 2013.