Robert Burns (1848). “The Complete Works of Robert Burns: With an Account of His Life, and a Criticism on His Writings. To which are Prefixed, Some Observations on the Character and Condition of the Scottish Peasantry”, p.256
Friedrich Nietzsche (2017). “THUS SPOKE ZARATHUSTRA (Modern Classics Series): The Magnum Opus of the World’s Most Influential Philosopher, Revolutionary Thinker and the Author of The Antichrist, The Birth of Tragedy & Beyond Good and Evil”, p.40, e-artnow