Kirana, Satria Andy. “Students’ Perception of Quipper As an Online Practice Tool for the English Computer-Based National Examination”. IJET (Indonesian Journal of English Teaching) 6, no. 2 (December 26, 2017): 248–264. Accessed February 23, 2026. https://jurnalftk.uinsa.ac.id/index.php/IJET/article/view/131.