Purwanto, Setiyo, Rachmat Abdul Gani, and Erna Suryani. “Characteristics of Ultisols Derived from Basaltic Andesite Materials and Their Association With Old Volcanic Landforms in Indonesia”. SAINS TANAH - Journal of Soil Science and Agroclimatology 17, no. 2 (December 30, 2020): 135–143. Accessed October 15, 2026. https://jurnal.uns.ac.id/tanah/article/view/38301.