Valencia, Regina, 		Trinovita, Elsa, 		Shinta, Herlina, 		Toemon, Angeline, AND 		Ysrafil, Ysrafil.
" Evaluation of the combination patch of betel leaf extract (Piper sp.) - ultrasonic assisted extraction as a transdermal delivery system on fibroblast cell formation and collagen density" <em>JURNAL ILMU KEFARMASIAN INDONESIA</em> [Online], Volume 23 Number 1 (30 April 2025)