Condensed Tannins Content and their Influence on the Antioxidant Activity of Bark Hydroethanol Extract of Piliostigma reticulatum (Dc) Hochst and its Fractions, DIENG, Serigne Ibra Mback, Mathieu Céline, SARR Abdou, Diatta-Badji Kady, and FALL Alioune Dior , Pharmacognosy Journal, March 2020, Volume 12, Issue 2, p.361-368, (2020)