Lukens-Bull, Ronald, and Kristen Angelucci Zahn. “The Linguistic Modeling of Variation in Islam: Constructing Saussure’s Concepts of Langue and Parole to Religious Studies”. Walisongo: Jurnal Penelitian Sosial Keagamaan, vol. 26, no. 1, July 2018, pp. 1-34, doi:10.21580/ws.26.1.2088.