Sulistiyono, Nurdin, et al. “Detection of Deforestation Using Low Resolution Satellite Images in the Islands of Sumatra 2000-2012”. International Journal of Sciences: Basic and Applied Research (IJSBAR), vol. 24, no. 1, Aug. 2015, pp. 350-66, https://gssrr.org/JournalOfBasicAndApplied/article/view/4457.