00503naa#a2200181#i#450# EN\INFRA-M\bibl\6182 20241108144132.5 1998-0728 20150617b2015####ek#y0engy0150####ca RUS RU Intellectual Marathon for Primary School Graduates Journal article Moscow INFRA-M Academic Publishing LLC. 2015 5 с. Journal article local Petlenko L. Romanova V. Yu. zh-szf.ru