Yüksel GÜMÜRDÜLÜ, et al. “Predictors of Vitamin B-12 Deficiency: Age and Helicobacter Pylori Load of Antral Mucosa”. Turkish Journal of Gastroenterology, vol. 14, no. 1, July 2019, pp. 44-49, https://turkjgastroenterol.avesjournals.com/index.php/tjg/article/view/1827.