Baillargeon, R. / 1991 / Reasoning about the height and location of hidden object in 4.5-6.5 month-old infants / Cognition 38 : 13 ~ 42 Berk, E. / 2006 / Child development / Pearson Bullock, M / 1999 / Scientific reasoning: Developmental and individual differences, In Individual development from 3 to 12: Findings from the Munich longitudinal study / Cambridge Univer Carey, S / 1985 / Are children fundamentally different thinkers and learners than adults?, In Thinking and learning skills(vol. 2) / Erlbaum Chinn, C. A. / 1993 / The role of anomalous data in knowledge acquistion: A theoretical framework and implications for science instruction / Review of Educational Research 6