1. The frequency of cerebral palsy: population studies in industrialized nations since 1950. In: eds. Epidemiology of the cerebral palsies. Philadelphia: J.B. Lippincott, 1984: 46-56
2. The natural history of cerebral palsy. Boston: Harvard University Press, 1959
3. Prenatal and perinatal risk factors in a survey of 681 Swedish cases. In: eds. Epidemiology of the Cerebral Palsies. Philadelphia: J.B. Lippincott, 1984: 116-134
4. Antecedents of Cerebral Palsy