Marcus Tullius Cicero (1856). “Cicero's Three books of Offices: or, Moral duties. Also his Cato Major, an essay on old age; Laelius, an essay on friendship; Paradoxes; Scipio's dream; and Letter to Quintus on the duties of a magistrate”, p.249
"Belief & Technique For Modern Prose: List of Essentials" in a letter to Arabelle Porter (28 May 1955); published in "Jack Kerouac: Selected Letters 1940-1956" by Jack Kerouac, 1995.