00621naa#a2200181#i#450# EN\\bibl\1164 20241225105739.3 2308-8877 20140207b2014####ek#y0engy0150####ca RUS RU Improving Operational Efficiency Transformers Used in Commercial Power Systems Journal article Voronezh FSBE Institution of Higher Education Voronezh State University of Forestry and Technologies named after G.F. Morozov 2014 9 с. Journal article local Gracheva Elena Mukhametzyanova Albina zh-szf.ru