Кобилін, П. О. “Functional and Component Structure of the Population Trading Service System”. Visnyk of V. N. Karazin Kharkiv National University, series "Geology. Geography. Ecology"0, no. 46 (November 1, 2017): 92-100. Accessed May 6, 2024. https://periodicals.karazin.ua/geoeco/article/view/9520.