Indira Anggriani, et al. “Analisis Kestabilan Model Penurunan Sumber Daya Hutan Akibat Industri”. Limits: Journal of Mathematics and Its Applications, vol. 15, no. 1, Mar. 2018, pp. 31-40, https://journal.its.ac.id/index.php/limits/article/view/5359.