00494naa#a2200169#i#450# EN\\bibl\2509 20241226031450.4 1995-0411 20140605b2014####ek#y0engy0150####ca RUS RU The economic potential of amateur tourism in Russia Journal article CHERKIZOVO Russian State University of Tourism and Service 2014 8 с. Journal article local Lepeshkin Vyacheslav naukaru.ru