Sokolov, Alexander A., Alexander A. Chibilev, and Oxana S. Rudneva. “Economic and Geographical Diff Erentiation of the Territory of the Russian-Kazakh Transboundary Area”. Proceedings of Voronezh State University. Series: Geography. Geoecology0, no. 4 (December 2, 2024): 85-92. Accessed December 5, 2025. https://journals.vsu.ru/geo/article/view/12702.