L. Azeez, A. O. Oyedeji, S. O. Adewuyi, and K. O. Tijani, “Syntheses, characterizations and antioxidant activities of copper complexes of quercetin as influenced by redox states”, Int. J. Bio. Chem. Sci, vol. 9, no. 5, pp. 2712–2718, Feb. 2016.