@article{del santoro_vallejos_almeida_2007,  title={Quantum baker maps for spiraling chaotic motion},  volume={37},  ISSN={0103-9733},  url={https://doi.org/10.1590/S0103-97332007000300016},  DOI={10.1590/S0103-97332007000300016},  number={2a},  journal={Brazilian Journal of Physics},  publisher={Sociedade Brasileira de Física},  author={del Santoro, Pedro R. and Vallejos, Raúl O. and Almeida, Alfredo M. Ozorio de},  year={2007},  month={Jun},  pages={440–445} }