Mat Rusni, Nur Arina, et al. “Mechanical Properties of Thulium-Doped Bismuth Borotellurite Glass via Nanoindentation for Lead-Free Radiation Shielding Application”. International Journal of Integrated Engineering, vol. 16, no. 6, Nov. 2024, pp. 206-15, https://penerbit.uthm.edu.my/ojs/index.php/ijie/article/view/18728.