00428naa#a2200145#i#450# EN\INFRA-M\bibl\122477 20260516034921.6 1998-0744 20260429b2026####ek#y0engy0150####ca RU Criteria for determining the levels of school Olympiads Journal article Moscow INFRA-M Academic Publishing LLC. 2026 2 с. Journal article local naukaru.ru