PATTERNS OF OCCURRENCE OF BIRTHS IN VICTORIA, AUSTRALIA, PRODUCING DOWN'S SYNDROME (MONGOLISM) AND CONGENITAL ANOMALIES OF THE CENTRAL NERVOUS SYSTEM: A 21-YEAR PROSPECTIVE AND RETROSPECTIVE SURVEY.

PATTERNS OF OCCURRENCE OF BIRTHS IN VICTORIA, AUSTRALIA, PRODUCING DOWN'S SYNDROME (MONGOLISM) AND CONGENITAL ANOMALIES OF THE CENTRAL NERVOUS SYSTEM: A 21-YEAR PROSPECTIVE AND RETROSPECTIVE SURVEY.