For citations:
Butorin N.N., Tsukanov V.V., Asyayev R.V., Butorina M.N., Vasyutin A.V., Tonkikh J.L. The frequency of ulcerative-erosive defects and ulcerative bleeding of the gastroduodenal zone in patients with coronavirus infection COVID-19. Experimental and Clinical Gastroenterology. 2022;(5):5-11. (In Russ.) https://doi.org/10.31146/1682-8658-ecg-201-5-5-11