@article{castro_2006,  title={NMR and FTIR characterization of petroleum residues: structural parameters and correlations},  volume={17},  ISSN={0103-5053},  url={https://doi.org/10.1590/S0103-50532006000600016},  DOI={10.1590/S0103-50532006000600016},  number={6},  journal={Journal of the Brazilian Chemical Society},  publisher={Sociedade Brasileira de Química},  author={Castro, Alexandre T.},  year={2006},  month={Sep},  pages={1181–1185} }