Sara Jeannette Duncan (2012). “A Voyage of Consolation (being in the nature of a sequel to the experiences of 'An American girl in London')”, p.165, tredition
Charles Darwin (2010). “The Works of Charles Darwin, Volume 29: “Erasmus Darwin” by Ernest Krause, with a Preliminary Notice by Charles Darwin; “The Autobiography of Charles Darwin” Edited by Nora Barlow; and Consolidated Index”, p.159, NYU Press