1. Brown, B. S. in Dyslexia: An Appraisal of Current Knowledge (eds Benton, A. L. & Pearl, D.) v–vii (Oxford University Press, 1978).
2. Critchley, M. in The Dyslexic Child (Heinemann, New York, 1970).
3. DeFries, J. C., Vogler, G. P. & LaBuda, M. C. in Perspectives in Behavior Genetics (eds Fuller, J. L. & Simmel, E. C.) 29–56 (Erlbaum, Hillsdale, 1986).
4. Smith, S. D. Genetics and Learning Disabilities (College-Hill, San Diego, 1986).
5. DeFries, J. C. & Fulker, D. W. Behav. Genet. 15, 467–473 (1985).