Sinambela, K. L., and D. C. Simanjuntak. “Study On The Use Of Oral Drills And Role-Play Method In Improving Students’ Interactive Speaking Achievement”. Acuity: Journal of English Language Pedagogy, Literature and Culture, vol. 2, no. 1, Jan. 2017, pp. 24-45, doi:10.35974/acuity.v2i1.586.