@article{pinto_oliveira_cavalli_giannini_2004,  title={Peroxide bleaching agent effects on enamel surface microhardness, roughness and morphology},  volume={18},  ISSN={1806-8324},  url={https://doi.org/10.1590/S1806-83242004000400006},  DOI={10.1590/S1806-83242004000400006},  number={4},  journal={Brazilian Oral Research},  publisher={Sociedade Brasileira de Pesquisa Odontológica - SBPqO},  author={Pinto, Cristiane Franco and Oliveira, Rogério de and Cavalli, Vanessa and Giannini, Marcelo},  year={2004},  month={Oct},  pages={306–311} }