Antecedents of Cerebral Palsy, Multivariate Analysis of Risk
NEJM 315:81-86, 124-1261986., Nelson,K.B.&Ellenberg,J.H., 1986
Neurological Follow-Up of 281 Children Born in Breech Presentation:A Controlled Study
BMJ 286:9-12, Faber-Nijhot,R.,et al, 1983