Ulbaek, I. (1998) The origin of language and cognition. 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.

Ulbaek, I. (1998) The origin of language and cognition. 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.

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