@article{matos_tarley_ferreira_arruda_2005,  title={Use of experimental design in the optimisation of a solid phase preconcentration system for Cobalt determination by GFAAS},  volume={30},  ISSN={0100-4670},  url={https://doi.org/10.1590/S0100-46702005000100009},  DOI={10.1590/S0100-46702005000100009},  number={1},  journal={Eclética Química},  publisher={Fundação Editora da Universidade Estadual Paulista Júlio de Mesquita Filho - UNESP},  author={Matos, G. D. and Tarley, C. R. T. and Ferreira, S. L. C. and Arruda, M. A. Z.},  year={2005},  pages={65–74} }