Berg, K A; Astemborski, J A; Boughman, J A et al. (1989) Congenital cardiovascular malformations in twins and triplets from a population-based study. Am J Dis Child 143:1461-3 |
Berg, K A; Clark, E B; Astemborski, J A et al. (1988) Prenatal detection of cardiovascular malformations by echocardiography: an indication for cytogenetic evaluation. Am J Obstet Gynecol 159:477-81 |