"The Individual in the Animal Kingdom" by Julian Huxley (1912) as quoted in Connie Barlow "From Gaia to Selfish Genes: Selected Writings in the Life Sciences", 1991.
Richard Cecil, Josiah PRATT (the Elder.) (1854). “Remains of the Rev. Richard Cecil ... With a view of his character, by the Rev. Josiah Pratt ... To which is prefixed a memoir of his life signed: J. Cecil . Tenth edition”, p.53
Sydney Smith, Sarah Austin, Lady Saba Smith Holland Holland (1855). “A Memoir of the Reverend Sydney Smith”, p.353, London, Longman, Brown, Green, and Longmans