Epidemiology of ischemic heart disease as related to the main risk factors among the male population in various Soviet cities (a cooperative study) | Epidemiologiia ishemicheskoǐ bolezni serdtsa i ee sviaz' osnovnymi faktorami riska sredi muzhskogo naseleniia v nekotorykh gorodakh SSSR (kooperativnoe issledovnaie)