00500naa#a2200181#i#450# EN\INFRA-M\bibl\15258 20241105161132.2 2306-627X 20161218b2016####ek#y0engy0150####ca RUS RU Theories of Investment Portfolio Optimization Journal article Moscow INFRA-M Academic Publishing LLC. 2016 6 с. Journal article local Nazarova Elena Zhdanova O. naukaru.ru