Thich Nhat Hanh (2008). “Present Moment Wonderful Moment: Mindfulness Verses for Daily Living: Easyread Super Large 18pt Edition”, p.31, ReadHowYouWant.com
Miyamoto Musashi, Yamamoto Tsunetomo, Inazo Nitobe (2010). “Honor: Samurai Philosophy of Life - The Essential Samurai Collection; The Book of Five Rings, Hagakure: The Way of the Samurai, Bushido: The Soul of Japan.”, p.75, Bottom of the Hill