Ron Paul's newsletter (1992), as quoted in "10 Extreme Claims in Ron Paul’s Controversial Newsletters" by Andy Kroll, www.motherjones.com. January 3, 2012.
Will Rogers, Bryan B. Sterling, Frances N. Sterling (1993). “Will Rogers' World: America's Foremost Political Humorist Comments on the Twenties and Thirties--and Eighties and Nineties”, p.23, Rowman & Littlefield