Helilusiatiningsih, Nunuk, et al. “Characterization and Antioxidant Activity Assay of Essential Oil Parts of Rosella (Hibiscus Sabdariffa L.)”. Jurnal Teknik Pertanian Lampung (Journal of Agricultural Engineering), vol. 13, no. 3, July 2024, pp. 671-8, doi:10.23960/jtep-l.v13i3.671-678.