John Stuart Mill (2017). “The Collected Works of John Stuart Mill: Utilitarianism, The Subjection of Women, On Liberty, Principles of Political Economy, A System of Logic, Ratiocinative and Inductive, Memoirs…”, p.189, e-artnow
James Mill (1829). “Essays on Government, Jurisprudence, Liberty of the Press, and Law of Nations. Written for the Supplement to the Encyclopædia Britannica”