Andre Setya Yudhanto, and Migunani. “PEMANFAATAN GLOBAL POSITIONING SYSTEM (GPS) PADA PRESENSI KARYAWAN BERBASIS SMARTPHONE”. Elkom : Jurnal Elektronika Dan Komputer, vol. 13, no. 2, Dec. 2020, pp. 139-50, https://journal.stekom.ac.id/index.php/elkom/article/view/307.