@article{maldacena_2004,  title={Strings in flat space and plane waves from N = 4 super Yang Mills},  volume={34},  ISSN={0103-9733},  url={https://doi.org/10.1590/S0103-97332004000200002},  DOI={10.1590/S0103-97332004000200002},  number={1a},  journal={Brazilian Journal of Physics},  publisher={Sociedade Brasileira de Física},  author={Maldacena, Juan},  year={2004},  month={Mar},  pages={151–156} }