1. Deep down in the jungle;Abrahams,1964
2. Talking hack;Abrahams,1976
3. American Speech-Language-Hearing Association (ASHA). National Court says IQ tests are biased. Asha, 1980, 22(1), 50.
4. Cross-cultural Piagetian research: An experimental perspective;Ashton;Harvard Educational Review,1975
5. Varieties of present-day English;Bailey,1973