David Washbrook, 'Lytton, Edward Robert Bulwer-, first earl of Lytton (1831–1891)', Oxford Dictionary of National Biography, Oxford University Press, Sept 2004; online edn, Jan 2008 accessed 29 September 2008
David Washbrook, 'Lytton, Edward Robert Bulwer-, first earl of Lytton (1831–1891)', Oxford Dictionary of National Biography, Oxford University Press, 2004; online edition, January 2008 accessed 2 November 2015