@article{li_liu_dai_dai_2020,  title={Tai Chi versus routine exercise in patients with early- or mild-stage Parkinson's disease: a retrospective cohort analysis},  volume={53},  ISSN={0100-879X},  url={https://doi.org/10.1590/1414-431X20199171},  DOI={10.1590/1414-431X20199171},  number={2},  journal={Brazilian Journal of Medical and Biological Research},  publisher={Associação Brasileira de Divulgação Científica},  author={Li, Quanhao and Liu, Jinmei and Dai, Fei and Dai, Fengling},  year={2020},  pages={e9171} }