Kharchenko, A., and A. Yelinska. “DNA Typing of the Gastric Mucosa of Patients With Chronic Duodenal Ulcer”. Journal of Education, Health and Sport 11, no. 11 (November 30, 2021): 221–230. Accessed April 18, 2025. https://apcz.umk.pl/JEHS/article/view/36455.