PERSPEKTIF OPERA BATAK SISINGAMANGARAJA XII EPISODE BORU LOPIAN ULUPORANG TANO BATAK. GR [Internet]. 2022 Jun. 30 [cited 2026 Apr. 22];11(1):123-37. Available from: https://jurnal.unimed.ac.id/2012/index.php/gorga/article/view/32473