@article{haselein_eckhard_2025,  title={Identification of a time-varying SIR Model for COVID-19},  volume={26},  ISSN={2676-0029},  url={https://doi.org/10.5540/tcam.2025.026.e01818},  DOI={10.5540/tcam.2025.026.e01818},  journal={Trends in Computational and Applied Mathematics},  publisher={Sociedade Brasileira de Matemática Aplicada e Computacional - SBMAC},  author={HASELEIN, W. M. and ECKHARD, D.},  year={2025},  pages={e01818} }