Togatorop, Firinta. “Politeness Strategies Used in the Conversation Between the Students of Finance and Banking Department in Murni Sadar Polytehnic Pematangsiantar”. Journal of English Teaching as a Foreign Language 5, no. 1 (June 30, 2019): 37-48. Accessed May 19, 2024. https://ejournal.uhn.ac.id/index.php/jetafl/article/view/115.