D. V. Shkurkin, O. V. Sogacheva, E. S. Logvencheva, and M. N. Khramova, “Modernization of the Sphere of Tourist and Hospitality Industry of the South of Russia as a Growth Factor of Socio-economic Stability of the Region”, IJEFI, vol. 6, no. 1S, pp. 101–106, May 2016.