@article{ibaceta_cornejo_ramirez_escobar_villagrán_schulz_2009,  title={Uso de morfina intratecal en artrodesis lumbar},  volume={8},  ISSN={1808-1851},  url={https://doi.org/10.1590/S1808-18512009000400007},  DOI={10.1590/S1808-18512009000400007},  number={4},  journal={Coluna/Columna},  publisher={Sociedade Brasileira de Coluna},  author={Ibaceta, Ronald Schulz and Cornejo, Nicolás Macchiavello and Ramirez, Sergio and Escobar, Jaime and Villagrán, Marcos Ganga and Schulz, Hermann},  year={2009},  month={Oct},  pages={386–389} }