P. Mikhnev, Ilya, Svetlana V. Mikhneva, and Natalia A. Salnikova. “Studies of Radon Activity in Civil Engineering and Environmental Objects”. International Journal of Engineering & Technology 7, no. 2.23 (April 20, 2018): 162–166. Accessed April 27, 2024. https://sciencepubco.com/index.php/ijet/article/view/11907.