Tomasello, M. (2003) On the different origins of symbols and grammar. In M.H. Christiansen and S. Kirby, editors, Language Evolution: The States of the Art . Oxford University Press.

Tomasello, M. (2003) On the different origins of symbols and grammar. In M.H. Christiansen and S. Kirby, editors, Language Evolution: The States of the Art. Oxford University Press.

Christiansen,Kirby, Language Evolution: Consensus and Controversies, 2003	::	14
Fitch, The Evolution of Language: A Comparative Review, 2005	::	2
Gardenfors,Warglien, Cooperation, Conceptual Spaces and the Evolution of Semantics, 2006	::
Hoefler,Smith, Reanalysis vs Metaphor: What Grammaticalisation CAN Tell Us about Language Evolution, 2008	::	1