Smetskov, D. A., T. P. Yavorskaya, and N. N. Goncharova. 2017. “Erosion Gastroduodenite – As a Complication After Operation in Perforate Ulcer Patients”. Journal of Education, Health and Sport 7 (9):601-5. https://apcz.umk.pl/JEHS/article/view/4929.