title: [Variations occurring in the mental working capacity of young schoolchildren during the school year].
mesh_terms: D000124:Achievement; D000367:Age Factors; D002648:Child; D006801:Humans; D007858:Learning / Q000502:physiology
vernacular_title: Izmenenie umstvennoĭ rabotosposobnosti uchashchikhsia nachal'nykh klassov v techenie uchebnogo goda.