Palm Oil Mill Efluent - Zeolite Mixture Improves Acid and Base Cations in Acid Sulfate Soil. j Trop. Soils [Internet]. 2020 Jan. 2 [cited 2025 Nov. 17];25(1):21-7. Available from: https://journal.unila.ac.id/index.php/tropicalsoil/article/view/345