N. Nazliniwaty and L. Laila, “Formulation and Antibacterial Activity of Plectranthus amboinicus (Lour.) Spreng Leaves Ethanolic Extract as Herbal Mouthwash Against Halitosis Caused Bacteria”, Open Access Maced J Med Sci, vol. 7, no. 22, pp. 3900–3903, Nov. 2019.