Dolgikh, V. T., and V. G. Epifanov. “Atrial Fibrillation and Condition of Vegetative Nervous System: Features of Tactics and Medical Aid Rendering at the Pre-Hospital Stage”. Patologicheskaya Fiziologiya I Eksperimental’naya Terapiya (Pathological physiology and experimental Therapy), vol. 59, no. 2, July 2015, pp. 34–39, https://pfiet.ru/article/view/857.