1. W. Whewell to P. M. Roget, 22 March 1831; Royal Society of London Library [DM/1].
2. J. W. Lubbock to W. Whewell, 27 January 1832; Trinity College Library, Cambridge [a/216/61].
3. George Greenough Papers; University College London [Add. 7918/1621].
4. Proc. R. Soc. Lond. 3, 140–155 (1832).
5. New Monthly Magazine 39, 2–6 (1833).