@article{morais_scalvi_martins_ribeiro_2006,  title={Analysis of Er3+ incorporation in SnO2 by optical investigation},  volume={36},  ISSN={0103-9733},  url={https://doi.org/10.1590/S0103-97332006000300010},  DOI={10.1590/S0103-97332006000300010},  number={2a},  journal={Brazilian Journal of Physics},  publisher={Sociedade Brasileira de Física},  author={Morais, Evandro A. de and Scalvi, Luis V. A. and Martins, Márcio R. and Ribeiro, Sidney J. L.},  year={2006},  month={Jun},  pages={270–273} }