F. H., Mohammed. A spectroscopic study of the effect of Er+3 ions concentration on the optical and structural properties of nanoTiO2. University of Thi-Qar Journal, [S. l.], v. 18, n. 1, 2023. Disponível em: https://www.jutq.utq.edu.iq/index.php/main/article/view/331. Acesso em: 22 nov. 2025.