@article{barrea_turner_2003,  title={Bounds for the subsistence of a problem of heat conduction},  volume={22},  ISSN={1807-0302},  url={https://doi.org/10.1590/S0101-82052003000200003},  DOI={10.1590/S0101-82052003000200003},  number={2},  journal={Computational & Applied Mathematics},  publisher={Sociedade Brasileira de Matemática Aplicada e Computacional},  author={Barrea, Andrés and Turner, Cristina},  year={2003},  pages={195–207} }