Dwi Septa Kariza, Riza, Asep Jamaludin, and Aji Perimajaya. 2022. “Expert System Diagnosing Gastroesophageal Reflux Disease (GERD) Using Certainty-Factor Method”. Jurnal Mantik 6 (3):3365-73. https://iocscience.org/ejournal/index.php/mantik/article/view/3130.