Spectroscopic investigations of Er2O3 doped silica borotellurite glasses. - Aliyu, Umar Sa'ad; Kamari, Halimah Mohamed; Geidam, Ibrahim Gana; Alade, Ibrahim Olanrewaju; Noorazlan, Azlan Muhammad; Hamza, Abdulkarim Muhammad; Ahmad, Ahmad Fahad (Optical Materials, 2021)