Puspitasari, Putri, et al., translators. “The Use of Formal and Informal Language Varieties in Internal Communication of the Deli Serdang Regency DPRD”. West Science Social and Humanities Studies , vol. 4, no. 05, May 2026, pp. 576-83, https://doi.org/10.58812/wsshs.v4i05.2843.