Suárez-Hernández, Laura, et al. “Morphological and Physicochemical Characterization of Biochar Produced by Gasification of Selected Forestry Species”. Revista Facultad De Ingeniería, vol. 26, no. 46, Sept. 2017, pp. 123-30, doi:10.19053/01211129.v26.n46.2017.7324.