[Reducing infant mortality in the Bulgarian People's Republic].
D002031:Bulgaria; D005260:Female; D006801:Humans; D007223:Infant; D007226:Infant Mortality; D007231:Infant, Newborn; D011247:Pregnancy; D012621:Seasons
Snizhenie detskoĭ smertnosti v Narodnoĭ Respublike Bolgarii.