Locke, J. L. (1998) Social sound-making as a precursor to spoken language. In Hurford, J. R. and Studdert-Kennedy, M. and Knight C., editors, Approaches to the Evolution of Language: Social and Cognitive Bases . Cambridge: Cambridge University Press.

Locke, J. L. (1998) Social sound-making as a precursor to spoken language. In Hurford, J. R. and Studdert-Kennedy, M. and Knight C., editors, Approaches to the Evolution of Language: Social and Cognitive Bases. Cambridge: Cambridge University Press.

2006	-	Language and life history: A new perspective on the development and evolution of human language - Locke,Bogin	::	2
		Locke, J. L. (1998c). Social sound-making as a precursor to spoken language. In Hurford, J. R., Studdert-Kennedy, M., & Knight, C. (Eds.), Approaches to the evolution of language: social and cognitive bases. Cambridge: Cambridge University Press.