@article{silva_m'peko_fontes_hernandes_2009,  title={Cation size effects-modified phase and PTCR development in Er3+ and Ca2+ co-doped BaTiO3 ceramics during sintering},  volume={12},  ISSN={1516-1439},  url={https://doi.org/10.1590/S1516-14392009000300007},  DOI={10.1590/S1516-14392009000300007},  number={3},  journal={Materials Research},  publisher={ABM, ABC, ABPol},  author={Silva, Ronaldo Santos da and M'Peko, Jean-Claude and Fontes, Lilian da Costa and Hernandes, Antonio Carlos},  year={2009},  month={Jul},  pages={287–290} }