@article{moraes_xavier_mendonça_araújo filho_oliveira_2011,  title={Chemical and structural characterization of soil humic substances under agroforestry and conventional systems},  volume={35},  ISSN={0100-0683},  url={https://doi.org/10.1590/S0100-06832011000500014},  DOI={10.1590/S0100-06832011000500014},  number={5},  journal={Revista Brasileira de Ciência do Solo},  publisher={Sociedade Brasileira de Ciência do Solo},  author={Moraes, Gislane M. de and Xavier, Francisco Alisson da Silva and Mendonça, Eduardo de Sá and Araújo Filho, João Ambrósio de and Oliveira, Teógenes Senna de},  year={2011},  month={Sep},  pages={1597–1608} }