[Premature children in a rural population of the Sierpc County in the years 1968-1972].
D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D011044:Poland; D012423:Rural Health; D012424:Rural Population
Losy wcześniaków w środowisku wiejskim w powiecie Sierpc w latach 1968-1972