AbstractGet full access to this articleView all access options for this article.Get accessReferences1. Clarke, A.D.B. : Journ. Mid. Ment. Def. Society, 1958, No. 4.2. Henderson and Gillespie : Textbook of Psychiatry, 9th Edition revised by Sir David Henderson and Ivor R.C. Batchelor. London: Oxford University Press, 1962.3. Penrose, L.S. : The Biology of Mental Defect. London: Sidgwick and Jackson Limited, 1963.4. Stott, D.H. : Lancet, 1957, 1, 1006.
