Barus, Aguslina Wati Kristina, Wisnu Hidayat, and Henny Arwina Bangun. “The Habit of Indiscriminate Spitting in Betel Chewing”. Jurnal Prima Medika Sains 5, no. 2 (December 10, 2023): 108-112. Accessed May 18, 2024. http://jurnal.unprimdn.ac.id/index.php/JPMS/article/view/4315.