DOBRUCALI, Ahmet, et al. “Fecal and Circulating TNF-a Measurement for Assessment of Disease Activity in Inflammatory Bowel Disease”. Turkish Journal of Gastroenterology, vol. 5, no. 3, Jan. 1994, pp. 461-5, https://www.turkjgastroenterol.org/index.php/tjg/article/view/481.