For citations:
Levina A.S., Babachenko I.V., Skripchenko N.V., Imyanitov E.N. The etiological structure of diseases in frequently ill children depending on age. Rossiyskiy Vestnik Perinatologii i Pediatrii (Russian Bulletin of Perinatology and Pediatrics). 2017;62(2):72-77. (In Russ.) https://doi.org/10.21508/1027-4065-2017-62-2-72-77