Hieu, L. T., L. L. Son, N. M. Nhung, H. X. A. Vu, and T. T. A. Thi. “Determination of Luteolin from Extracts of Helicteres Hirsuta by HPLC”. Hue University Journal of Science: Natural Science, vol. 128, no. 1B, July 2019, pp. 43-47, doi:10.26459/hueuni-jns.v128i1B.5195.