A. Rahmadani, R. Ridwanto, A. S. Daulay, and H. M. Nasution, “Determination of total flavonoid content in 70% ethanol extract and ethyl acetate extract of sambung nyawa Leaves (Gynura procumbens (Lour) Merr.) using UV-Vis spectrophotometry”, JPS, vol. 8, no. 1, pp. 114–128, Feb. 2025.