References
Eve V. Clark
(1970-1979)
X(1971). On the acquisition of the meaning of before and after. Journal of learning and verbal behaviour, 10, 266-275.
(1973). What's in a word?: on the child's acquisition of semantics in his first language. In T. E. Moore (Ed.). Cognitive development and the acquisition of language (pp. 65-110). London-New York: Academic Press.