Retnaningsih, W., Nugroho, A., Van, D. T. H., & Al Amin, N. H. (2022). Booming the Vocabulary Acquisition by Using Flipped Classroom on EFL Learners’ PPA (Performance, Perception and Acceptance). Voices of English Language Education Society, 6(2), 325–339. https://doi.org/10.29408/veles.v6i2.6107