D. S. Siregar, Rosmayati, R. S. Pirngadi, and Anggreiny, “Farmer empowerment through training on palm sugar standardization in Eastern Coastal Region of North Sumatera ”, ABDIMAS J. Pengabdi. Masy. Univ. Merdeka Malang, vol. 11, no. 1, pp. 26–39, Feb. 2026.