Dafisco, Rafli, Serli Wulandari, and Nana Fitriana Arifin. 2025. “Gambir, Timber and Coffee: A History of the Trade in Forest and Plantation Products on the East Coast of Sumatra in the 19th Century”. Journal of Philology and Historical Review 2 (2):151-63. https://doi.org/10.61540/jphr.v2i2.99.