Channa, Naseem Aslam, et al. “ASSOCIATION OF TEA AND OTHER ADDICTIVE SUBSTANCES WITH GALLSTONE DISEASE IN SOUTHERN SINDH, PAKISTAN: Association of Tea With Gallstone Disease”. Pakistan Armed Forces Medical Journal, vol. 58, no. 4, Dec. 2008, pp. 363-71, https://pafmj.org/PAFMJ/article/view/1901.