@article{reis_malabarba_1987,  title={Revision of the neotropical cichlid genus Gymnogeophagus Ribeiro, 1918, with descriptions of two new species (Pisces, Perciformes)},  volume={4},  ISSN={0101-8175},  url={https://doi.org/10.1590/S0101-81751987000400002},  DOI={10.1590/S0101-81751987000400002},  number={4},  journal={Revista Brasileira de Zoologia},  publisher={Sociedade Brasileira de Zoologia},  author={Reis, R. E. and Malabarba, L. R.},  year={1987},  pages={259–305} }