REFERENCES
- Fantini , A.E. 1985 . Language Acquisition of a Bilingual Child: a sociolinguistic perspective , Clevedon : Multilingual Matters Ltd. .
- Halliday , M.A.K. 1971 . Explorations in the Functions of Language , New York : Elsevier .
- Skinner , B.F. 1957 . Verbal Behaviour , New York : Appleton Century Crofts .