“FORMULATION AND PHYSICAL STABILITY TESTING OF A FACIAL SERUM GEL CONTAINING GOTU COLA (Centella asitica (L.)) LEAF EXTRACT WITH VARIYING OF CARBOMER CONCENTRATIONS AS A GELLING AGENT”. Proceedings OPTIMAL, vol. 3, no. 1, Feb. 2026, https://doi.org/10.5281/2cjphb02.