Knight, C. (2000) Play as a precursor of phonology and syntax. In Chris Knight and James R. Hurford and Michael Studdert-Kennedy, editors, The Evolutionary Emergence of Language: Social Function and the Origins of Linguistic Form . Cambridge: Cambridge University Press.

Knight, C. (2000) Play as a precursor of phonology and syntax. In Chris Knight and James R. Hurford and Michael Studdert-Kennedy, editors, The Evolutionary Emergence of Language: Social Function and the Origins of Linguistic Form. Cambridge: Cambridge University Press.

2003	-	The Language Mosaic and its Evolution - Hurford	::	5
		----- 2000. Play as precursor of phonology and syntax. In C.Knight, M.Studdert-Kennedy, and J.R. Hurford (Eds.), The Evolutionary Emergence of Language: Social Function and the Origins of Linguistic Form, Cambridge: Cambridge University Press. 99-119.