RT Journal Article SR Electronic T1 Mongolism and maternal menarche. JF Journal of Medical Genetics JO J Med Genet FD BMJ Publishing Group Ltd SP 135 OP 136 DO 10.1136/jmg.6.2.135 VO 6 IS 2 A1 Berg, J M A1 Bavin, J T YR 1969 UL http://jmg.bmj.com/content/6/2/135.abstract AB