Windarto, Yudi Eko, et al. “Sistem Pakar Diagnosis Penyakit Gastritis Menggunakan Metode Certainty Factor Berbasis Android”. Jurnal Transformatika, vol. 18, no. 1, July 2020, pp. 36-55, https://doi.org/10.26623/transformatika.v18i1.2088.