Hadiatmi, I., S. Wilian, and K. . Yusra. “Classroom Languages As Used By English Teachers At An Indonesian Junior High School In Smpn 1 Keruak”. Jurnal Ilmiah Pendidikan Indonesia, vol. 2, no. 1, June 2020, pp. 81-90, https://jipi.unram.ac.id/index.php/jipi/article/view/40.