Sorensen HT, Sabroe S, Olsen J, Rothman KJ, Gillman MW, Fisher P. Birth weight as a predictor of young men's intelligence. A historical cohort study. Ugeskr Laeger. 1999 Feb 8;161(6):791-3.
Pueschel SM, Rothman KJ, Ogilby JD. Birth weight of children with down's syndrome. Am J Ment Defic. 1976 Jan;80(4):442-5.