@article{riveros_tenenblat_2003,  title={On four dimensional Dupin hypersurfaces in Euclidean space},  volume={75},  ISSN={0001-3765},  url={https://doi.org/10.1590/S0001-37652003000100001},  DOI={10.1590/S0001-37652003000100001},  number={1},  journal={Anais da Academia Brasileira de Ciências},  publisher={Academia Brasileira de Ciências},  author={RIVEROS, CARLOS M. C. and TENENBLAT, KETI},  year={2003},  month={Mar},  pages={1–7} }