@article{urquieta-gonzález_martins_peguin_batista_2002,  title={Identification of Extra-Framework Species on Fe/ZSM-5 and Cu/ZSM-5 Catalysts Typical Microporous Molecular Sieves with Zeolitic Structure},  volume={5},  ISSN={1516-1439},  url={https://doi.org/10.1590/S1516-14392002000300017},  DOI={10.1590/S1516-14392002000300017},  number={3},  journal={Materials Research},  publisher={ABM, ABC, ABPol},  author={Urquieta-González, E.A. and Martins, L. and Peguin, R.P.S. and Batista, M.S.},  year={2002},  month={Jul},  pages={321–327} }