JOHN, R.; RAJAKUMARI, R. Synthesis and Characterization of Rare Earth Ion Doped Nano ZnO. Nano-Micro Letters, [S. l.], v. 4, n. 2, p. 65-72, 2012. DOI: 10.1007/BF03353694. Disponível em: https://www.nmlett.org/index.php/nml/article/view/706. Acesso em: 4 may. 2024.