[On the characteristics of natural ultraviolet radiation in Leningrad].
D004781:Environmental Exposure; D004782:Environmental Health; D006801:Humans; D012426:Russia; D013472:Sunlight; D014466:Ultraviolet Rays / Q000145:classification*
K kharakteristike estestvennoĭ ul'trafioletovoĭ radiatsii v Leningrade.