Bryan W. Van Norden. Introduction to Classical Chinese Philosophy. (Indianapolis: Hackett, 2011; ISBN9781603844697), p. 53, sourcing Fred R. Shapiro, ed., The Yale Book of Quotations (New Haven: Yale University Press 2006), p. 669. Archived October 6, 2014, at the Wayback Machine
Stevenson, Burton (1949). Stevenson's book of proverbs, maxims and familiar phrases. London: Routledge and Kegan Paul. p. 2611.
Bryan W. Van Norden. Introduction to Classical Chinese Philosophy. (Indianapolis: Hackett, 2011; ISBN9781603844697), p. 53, sourcing Fred R. Shapiro, ed., The Yale Book of Quotations (New Haven: Yale University Press 2006), p. 669. Archived October 6, 2014, at the Wayback Machine