Levels of thorium, uranium and potassium in Brazilian geological sediment determined by gamma-ray spec-troscopy and instrumental neutron activation analysis. Braz. J. Rad. Sci. [Internet]. 2023 Jan. 4 [cited 2025 May 2];10(3B (Suppl.). Available from: https://www.bjrs.org.br/revista/index.php/REVISTA/article/view/1984