Siregar, Sakinah, and Yahfizham Yahfizham. “Etnomatematika Pada Transaksi Jual Beli Masyarakat Pesisir Di Sibolga”. Jurnal Cendekia : Jurnal Pendidikan Matematika 7, no. 2 (June 30, 2023): 1877-1889. Accessed October 8, 2025. https://j-cup.org/index.php/cendekia/article/view/2251.