For citations:

Spivak E.M., Nikolaeva T.N., Klimachev A.M. Specific features of the clinical manifestations of patent ductus arteriosus in extremely premature newborns. Rossiyskiy Vestnik Perinatologii i Pediatrii (Russian Bulletin of Perinatology and Pediatrics). 2016;61(1):51-55. (In Russ.) https://doi.org/10.21508/1027-4065-2016-61-1-51-55