Ballard, D.H., Hayhoe, M.M., Pook, P.K. & Rao, R.P.N. (1997), Deictic codes for the embodiment of cognition. Behavioral and Brain Sciences, 20(4), 723-742.

Cowan, N. (2001). The magical number 4 in short-term memory: A reconsideration of mental storage capacity. Behavioral and Brain Sciences, 24 (1), 87-114.

Culham, J.C., Brandt, S.A., Cavanagh, P., Kanwisher, N.G., Dale,A.M. & Tootell, R.B.H. (1998). Cortical fMRI Activation Produced by Attentive Tracking of Moving Targets. Journal of Neurophysiology, 80, 2657-2670.

Dehaene, S. (1997). The Number Sense. New York: Oxford University Press.

Dennett, D. (1996). Kinds of Minds . London: Weidenfeld and Nicolson.

Herrnstein, R. (1991). Levels of categorization. In G. Edelman, W. Gall, & W. Cowan (Eds.), Signal and Sense, pp. 385--413. Somerset, NJ: Wiley-Liss.

Hurford, J. R. (1999). Individuals are abstractions. Behavioral and Brain Sciences, 22(4) 620-621.

Hurford, J. R. (2001). Protothought had no logical names. In J.Trabant & S.Ward (Eds.), New Essays on the Origin of Language . pp. 119-132. Berlin: de Gruyter

Hurford, J. R. (2003). The Neural Basis of Predicate-Argument Structure, Behavioral and Brain Sciences, 26(3),261-283.

Johansson, G. (1973), Visual perception of biological motion and a model for its analysis. Perception and Psychophysics, 14 201--211.

Miller, G. (1956). The magical number seven, plus or minus two: Some limits on our capacity for processing information. Psychological Review, 63, 81-97.

Parsons, T. (1990). Events in the Semantics of English: a Study in Subatomic Semantics. Cambridge, MA: MIT Press.

Vallortigara, G., Regolin, L. & Marconato, F. (2005), Visually inexperienced chicks exhibit spontaneous preference for biological motion patterns. PLoS Biology, 3(7), e208. (Public Library of Science, online journal).

Zuberbühler, K., Cheney, D.L., & Seyfarth, R.M. (1999). Conceptual semantics in a nonhuman primate. Journal of Comparative Psychology, 113(1), 33-42.