«The Aqueous Calyx Extract of Hibiscus sabdariffa Lowers Blood Pressure and Heart Rate via Sympathetic Nervous System Dependent Mechanisms» (2021) Nigerian Journal of Physiological Sciences, 29(2), or. 131–136. Available at: https://ojshostng.com/index.php/njphysiologicalsciences/article/view/1820 (Eskuratua: 16 maiatza 2026).