Panda, N. C., B. K. Sahu, S. K. Panda, and A. G. Rao. “Damage Done to Intestine, Liver and Kidneys by Tannic Acid of Tea and Coffee”. The Indian Journal of Nutrition and Dietetics, vol. 18, no. 3, Mar. 1981, pp. 97-103, https://www.informaticsjournals.com/index.php/ijnd/article/view/12802.