00539naa#a2200169#i#450# EN\\bibl\6896 20240504073358.6 1995-0411 20150904b2015####ek#y0engy0150####ca RUS RU Development trends of sanatorium and resort services market in Central Federal District Journal article CHERKIZOVO Russian State University of Tourism and Service 2015 7 с. Journal article local Oborin Matvey Sergeevich rguts.editorum.ru