Syahara, Muhammad Alwi, Nunuk Helilusiatiningsih, and Titik Irawati. “Antioxidant Activity Assay of Roselle (Hibiscus Sabdariffa) Seeds Ethanol Extract With DPPH Radical Scavenging Using UV-Vis Spectrophotometer”. Journal of Natural Sciences and Mathematics Research 10, no. 1 (July 19, 2024): 46–54. Accessed June 25, 2025. https://journal.walisongo.ac.id/index.php/JNSMR/article/view/20515.