M. A. Syahara, N. Helilusiatiningsih, and T. Irawati, “Antioxidant activity assay of Roselle (Hibiscus sabdariffa) seeds Ethanol extract with DPPH radical scavenging using UV-Vis Spectrophotometer”, J. Nat. Scien. & Math. Res., vol. 10, no. 1, pp. 46–54, Jul. 2024.