Al-maliki, Firas J. “Synthesis of Nanosilica Glass Activated by Erbium Ions, Spectroscopic Studies”. Iraqi Journal of Physics 7, no. 8 (December 30, 2009): 85–92. Accessed December 23, 2024. https://ijp.uobaghdad.edu.iq/index.php/physics/article/view/921.