Lubis AI, Gaol NYL. Application of Certainty Factor Method in Intelligent System for Diagnosis of Periodontal Disease in Cigarette AddictsApplication of Certainty Factor Method in Intelligent System for Diagnosis of Periodontal Disease in Cigarette Addicts. SinkrOn [Internet]. 2022Oct.3 [cited 2024Jul.16];6(4):2272-9. Available from: https://jurnal.polgan.ac.id/index.php/sinkron/article/view/11695