title: [Comparative clinical considerations on influenza epidemics in 1952, 1957 and 1959 in our country according to data of the internal clinic of the Sofia Higher Medical Institute].
mesh_terms: D000047:Academies and Institutes; D000554:Ambulatory Care Facilities; D006801:Humans; D007251:Influenza, Human / Q000453:epidemiology*
keywords: INFLUENZA/epidemiology