CHHETRI, R. P. Background Radiation: Detection, Measurement and Hazards. Himalayan Physics, [S. l.], v. 6, p. 119–122, 2017. DOI: 10.3126/hj.v6i0.18375. Disponível em: https://www.nepjol.info/index.php/HP/article/view/18375. Acesso em: 9 dec. 2021.