1. Bellwood, P. in The Origins and Spread of Agriculture and Pastoralism in Eurasia (ed. Harris, D. R.) 465-498 (UCL Press, London, 1996).
2. Renfrew, C. in The Origins and Spread of Agriculture and Pastoralism in Eurasia (ed. Harris, D. R.) 70-92 (UCL Press, London, 1996).
3. Bellwood, P. Sci. Am. 265 (1), 88-93 (1991).
4. Renfrew, C. Archaeology and Language: The Puzzle of Indo-European Origins (Cape, London, 1987).
5. Cavalli-Sforza, L. L., Piazza, A. & Menozzi, P. The History and Geography of Human Genes (Princeton Univ. Press, 1994).