1. BETHELL, L., 1970 The abolition of the Brazilian slave trade. Cambridge University Press. Pp 425.
2. BROWNE, J., 1995 Charles Darwin. Voyaging. Jonathan Cape, London. Pp 605.
3. BURCHELL, W.J., 1822, 1824 Travels in the interior of southern Africa. London. Vol. 1 pp 582, Vol. 2 pp 648. (Second volume is dated 1824 but was published in 1823).
4. BUSHNELL, D. and MACAULAY, N., 1994 The Emergence of Latin America in the nineteenth century. Oxford University Press. 2nd edn. Pp 341.