John Locke, Ruth Weissbourd Grant, Nathan Tarcov (1996). “Some Thoughts Concerning Education: And, Of the Conduct of the Understanding”, Hackett Publishing
Erma Bombeck (2013). “The Erma Bombeck Collection: If Life Is a Bowl of Cherries, What Am I Doing in the Pits?, Motherhood, and The Grass Is Always Greener Over the Septic Tank”, p.268, Open Road Media
John Muir (2015). “A Thousand-Mile Walk to the Gulf (With Original Drawings & Photographs): Adventure Memoirs, Travel Sketches & Wilderness Studies”, p.43, e-artnow