E. V. Gavrilyuk, Y. Y. Boeva, I. Anyasi, M. S. Maltseva, and D. .E. Volkov, “CLINICAL CASE OF PERSISTENT ATRIAL FLUTTER IN PATIENT WITH COMORBID PATHOLOGY”, J. V. N. Karazin Khark. Nat. Univ., Ser. Med., no. 26, pp. 66-70, Jul. 2015.