Purba, Rudiarman. “Lexical Variation on Students’ Daily Conversation at Campus by First Year Students of English Department FKIP HKBP Nommensen University”. Journal of English Teaching as a Foreign Language 1, no. 2 (December 22, 2015): 60-76. Accessed May 19, 2024. https://ejournal.uhn.ac.id/index.php/jetafl/article/view/314.