BabienkoV. V., ShanyhinA. V., and BabichM. S. “Estimation of Efficiency of Combined Therapy of Vitamin D Deficiency Conditions by Combining Cholecalcipherol Drugs and Correction of Nutritive Status ”. Health, Physical Culture and Sports, Vol. 19, no. 3, June 2020, pp. 17-30, https://hpcas.ru/article/view/8128.