@article{bellavia_porcelli_2014,  title={PRECONDITIONING ISSUES IN THE NUMERICAL SOLUTION OF NONLINEAR EQUATIONS
               AND NONLINEAR LEAST SQUARES},  volume={34},  ISSN={0101-7438},  url={https://doi.org/10.1590/0101-7438.2014.034.03.0421},  DOI={10.1590/0101-7438.2014.034.03.0421},  number={3},  journal={Pesquisa Operacional},  publisher={Sociedade Brasileira de Pesquisa Operacional},  author={Bellavia, Stefania and Porcelli, Margherita},  year={2014},  month={Sep},  pages={421–445} }