Nurmawati, N., H. Atmowardoyo, and S. Weda. “An Analysis of Positive Politeness Strategies to Promote Effective Interaction in The Classroom”. ELS Journal on Interdisciplinary Studies in Humanities, vol. 2, no. 2, June 2019, pp. 171-8, doi:10.34050/els-jish.v2i2.6340.