W. A. . WAN SUKAIRI, L. CHE ROSE, A. . ASARI, and R. . MOHD RAZALI, “CORRELATION BETWEEN TPC AND TFC WITH ANTIOXIDANT ACTIVITY OF Piper sarmentosum EXTRACT AND ITS FORMULATION FOR COSMETIC PURPOSES”, UMT JUR, vol. 3, no. 2, pp. 51–60, Apr. 2021.