Vitalia Hanako Murni Simanjuntak, and Fernando De Napoli Marpaung. “Threats and Preservation Efforts of Local Languages in a Heterogeneous City: A Case Study of Medan, North Sumatra”. Prosiding Seminar Nasional Riset Bahasa Dan Pengajaran Bahasa, vol. 7, no. 1, Dec. 2025, pp. 98-107, doi:10.31940/senarilip.v7i1.98-107.