@article{paiva_martins_siqueira_2007,  title={Analysis of ortho-cresol in urine by solid phase microextraction-capillary gas chromatography},  volume={18},  ISSN={0103-5053},  url={https://doi.org/10.1590/S0103-50532007000500024},  DOI={10.1590/S0103-50532007000500024},  number={5},  journal={Journal of the Brazilian Chemical Society},  publisher={Sociedade Brasileira de Química},  author={Paiva, Maria José N. de and Martins, Isarita and Siqueira, Maria Elisa P. B. de},  year={2007},  pages={1034–1039} }