Davidson, I. (2003) The archaeological evidence of language origins: States of the art. In M.H. Christiansen and S. Kirby, editors, Language Evolution: The States of the Art . Oxford University Press.

Davidson, I. (2003) The archaeological evidence of language origins: States of the art. In M.H. Christiansen and S. Kirby, editors, Language Evolution: The States of the Art. Oxford University Press.

2003	-	Language Evolution: Consensus and Controversies - Christiansen,Kirby	::	14
2008	-	Language as shaped by the brain - Christiansen,Chater	::	5