1. Acredolo, L. P., & Goodwyn, S. W. (1988). Symbolic gesturing in normal infants.Child Development, 59 450?456.
2. Bakeman, R., & Gottman, J. M. (1986).Observing interaction: An introduction to sequential analysis. New York: Cambridge University Press.
3. Bates, E. (1979).The emergence of symbols: Cognition and communication in infancy. New York: Academic Press.
4. Bates, E., Benigni, L., Bretherton, I., Camaioni, L., & Volterra, V. (1977). From gesture to the first word: On cognitive and social prerequisites. In M. Lewis & L. Rosenblum (Eds.),Interaction, conversation, and the development of language (pp. 247?307). New York: Wiley.
5. Bates, E., Bretherton, I., Snyder, L., Shore, C., & Volterra, V. (1980). Vocal and gestural symbols at 13 months.Merrill-Palmer Quarterly, 26 407?423.