Fitriani Sammulia, S., Sri Rachmayanti , A. and Lam Parulian Tampubolon , J. 2023. Optimization of HPMC as Gelling Agent in Gel Formula of Etanol Extract of Bangun-Bangun Leaves (Plectranthus amboinicus (Lour) Spreng). Jurnal EduHealth. 14, 01 (Feb. 2023), 160–166.