Miyamoto Musashi (2013). “The Book of Five Rings: A Text on Kenjutsu and the Martial Arts in General, Written by the Swordsman Miyamoto Musashi”, p.31, Lulu Press, Inc
Samuel Johnson (1787). “The Works of Samuel Johnson, LL.D.: Together with His Life, and Notes on His Lives of the Poets, by Sir John Hawkins, Knt. In Eleven Volumes ...”, p.136