Corncob-Derived Sulfonated Magnetic Solid Catalyst Synthesis as Heterogeneous Catalyst in The Esterification of Waste Cooking Oil and Bibliometric Analysis. Indonesian J. Sci. Technol [Internet]. 2024 Jul. 19 [cited 2025 Sep. 6];9(1):109-24. Available from: https://ejournal.kjpupi.id/index.php/ijost/article/view/349