Haryati, H., and R. Prayuana. “An Analysis of Code-Mixing Usage in WhatsApp Groups Conversation Among Lecturers of Universitas Pamulang”. Ethical Lingua: Journal of Language Teaching and Literature, Vol. 7, no. 2, Oct. 2020, pp. 236-50, https://ethicallingua.org/25409190/article/view/180.