@article{flores-riveros_rivas-silva_1999,  title={Variational description of the 3-body Coulomb problem through a correlated Eckart-Gaussian wavefunction},  volume={29},  ISSN={0103-9733},  url={https://doi.org/10.1590/S0103-97331999000300018},  DOI={10.1590/S0103-97331999000300018},  number={3},  journal={Brazilian Journal of Physics},  publisher={Sociedade Brasileira de Física},  author={Flores-Riveros, A. and Rivas-Silva, J. F.},  year={1999},  month={Sep},  pages={529–540} }