[Twin births in Belgium (1960-1961). A statistical study].
D000293:Adolescent; D000328:Adult; D001530:Belgium; D001722:Birth Order; D005260:Female; D006801:Humans; D008297:Male; D008423:Maternal Age; D008875:Middle Aged; D010298:Parity; D011247:Pregnancy; D012744:Sex Ratio; D013223:Statistics as Topic; D014427:Twins
Les naissances gémellaires en Belgique (1960-1961). Etude statistique.