@article{dittmar_2010,  title={Revista Coluna/Columna y SILACo},  volume={9},  ISSN={1808-1851},  url={https://doi.org/10.1590/S1808-18512010000300001},  DOI={10.1590/S1808-18512010000300001},  number={3},  journal={Coluna/Columna},  publisher={Sociedade Brasileira de Coluna},  author={Dittmar, Michael},  year={2010},  month={Jul},  pages={ix–ix} }