Tarigan EB. Expert System for Diagnosis of Pests and Diseases of Citrus Plants using the Certainty Factor Method (Case Study in Deram Village, Karo Regency). ijobas [Internet]. 2021 Jun. 30 [cited 2026 Apr. 16];10(1):9-15. Available from: https://www.ijobas.pelnus.ac.id/index.php/ijobas/article/view/1