(1987) Factors influencing the development of language proficiency. In D. Nunan (ed.) Applying second language acquisition research. Adelaide, National Curriculum and Resources Centre: 45–141.
(1983) Age differences in second language acquisition: research findings and folk psychology. In K. Bailey , M. Long and S. Peck (eds) Second language acquisition studies. Rowley, Mass., Newbury House: 141–150.
(1979) Individual differences in second language acquisition. In C. Fillmore , D. Kempler and W. Wang (eds) Individual differences in language ability and language behaviour. New York, Academic Press: 203–228. doi: 10.1016/B978‑0‑12‑255950‑1.50017‑2