Tagonna E. Siburian, Ely Djulia and Widya Arwita (2026) “Development of a Non-Textbook on Biodiversity in Sumatra Based on the Sustainable Development Goals to Improve Critical Thinking and Problem-Solving Skills”, Jurnal Perspektif, 10(1), pp. 137–151. doi: 10.15575/jp.v10i1.446.