For citations:
Maltsev S.V., Zakirova A.M., Mansurova G.Sh. Vitamin D provision in children of different age groups during the winter season. Rossiyskiy Vestnik Perinatologii i Pediatrii (Russian Bulletin of Perinatology and Pediatrics). 2017;62(2):99-103. (In Russ.) https://doi.org/10.21508/1027-4065-2017-62-2-99-103