SOYKAN, İrfan, et al. “The Effect of Different Dosage and Duration of Lansoprazole-Clarithromycin- Amoxycillin Combination on Helicobacter Pylori Eradication”. Turkish Journal of Gastroenterology, vol. 10, no. 2, Jan. 1999, pp. 115-7, https://www.turkjgastroenterol.org/index.php/tjg/article/view/960.