[ON CURRENT PROBLEMS IN THE EPIDEMIOLOGY OF WHOOPING COUGH].
D003604:Czechoslovakia; D004813:Epidemiology; D006801:Humans; D014917:Whooping Cough
CZECHOSLOVAKIA; EPIDEMIOLOGY; WHOOPING COUGH
K SOU CASN'E PROBLEMATICE EPIDEMIOLOGIE D'AVIV'EHO KA SLE.