Alfiany, F. et al. 2021. Optimasi Basis Formulasi Sediaan Handsanitizer Gel Ekstrak Daun Sirih Hitam (Piper betle var nigra) Sebagai Antibakteri: Optimization of the Hand Sanitizer Gel Preparation Base for Black Betel Leaf Extract (Piper betle var nigra) as an antibacterial. Proceeding of Mulawarman Pharmaceuticals Conferences. 14, 1 (Dec. 2021), 186–189. DOI:https://doi.org/10.25026/mpc.v14i1.556.