Determination of the activity concentration of 226Ra, 232Th, 40K and the concentration of 222Rn in soil samples of the Campos Gerais region (Paraná). Braz. J. Radiat. Sci. [Internet]. 30 de abril de 2021 [citado 21 de julio de 2025];9(1A). Disponible en: https://www.bjrs.org.br/revista/index.php/REVISTA/article/view/1240