Palacios, I. et al. 2021. Pixel Purity Index Applied to the Mapping of Degraded Soils by the Presence of Cangahuas in the Ilaló Volcano, Ecuador. International Journal on Advanced Science, Engineering and Information Technology. 11, 5 (Oct. 2021), 2121–2127. DOI:https://doi.org/10.18517/ijaseit.11.5.14684.