Purba, Nurcintama, et al. “EXPLORING ISLAMIC TRACES IN TAPANULI THROUGH THE BONGAL SITE: HISTORY, IDENTITY AND CULTURAL HERITAGE”. SOSIOEDUKASI : JURNAL ILMIAH ILMU PENDIDIKAN DAN SOSIAL, vol. 15, no. 2, June 2026, pp. 3327-36, doi:10.36526/sosioedukasi.v15i2.8436.