@article{llerena jr._almeida_1998,  title={Cytogenetic and molecular contributions to the study of mental retardation},  volume={21},  ISSN={1415-4757},  url={https://doi.org/10.1590/S1415-47571998000200018},  DOI={10.1590/S1415-47571998000200018},  number={2},  journal={Genetics and Molecular Biology},  publisher={Sociedade Brasileira de Genética},  author={Llerena Jr., Juan C. and Almeida, José Carlos Cabral de},  year={1998},  month={Jun},  pages={273–279} }