“Response of Maize to Humic Acid and Foliar Salicylic Acid Application”, IJSR, vol. 1, no. 2, hlm. 139–150, Okt 2024, Diakses: Nov 02, 2026. Tersedia pada: https://www.penerbitjurnalinternasional.com/index.php/ijsr/article/view/724