@article{guarino_gil_polivanov_menezes_1997,  title={Characterization of a brazilian smectite by solid state NMR and X-ray diffraction techniques},  volume={8},  ISSN={0103-5053},  url={https://doi.org/10.1590/S0103-50531997000600004},  DOI={10.1590/S0103-50531997000600004},  number={6},  journal={Journal of the Brazilian Chemical Society},  publisher={Sociedade Brasileira de Química},  author={Guarino, Alcides Wagner Serpa and Gil, Rosane A. S. San and Polivanov, Helena and Menezes, Sonia M.C.},  year={1997},  pages={581–586} }