00599naa#a2200181#i#450# EN\\bibl\12914 20240513121310.1 1999-5644 20160915b2016####ek#y0engy0150####ca RUS RU CONDITIONS AND PREREQUISITES OF DEVELOPMENT OF CLUSTERS IN THE SPHERE OF YOUTH TOURISM IN THE NORTH-WEST FEDERAL DISTRICT Journal article CHERKIZOVO Russian State University of Tourism and Service 2016 8 с. Journal article local Grishin Sergey Karpova Galina rguts.editorum.ru