Batu Bara, B. P., M. I. Wahyuddin, and A. Iskandar. “Development of Online Academic Portal System Android Based on National University: Development of Online Academic Portal System Android Based on National University”. Jurnal Mantik, vol. 4, no. 1, May 2020, pp. 751-9, https://www.iocscience.org/ejournal/index.php/mantik/article/view/848.