TY  - BOOK
AU  - Singleton,David
TI  - Language acquisition: the age factor 
T2  - Multilingual matters
SN  - 1-85359-019-3
U1  - 401, .9 19
PY  - 1989///
CY  - Clevedon
PB  - Multilingual Matters
KW  - Language acquisition
KW  - Lenguas
KW  - Estudio y enseñanza
N1  - Includes bibliography and index
ER  -