Krupko, Anatoliy E., and Yuri M. Fetisov. “Mathematical Modelling of the Economy of the Central Black Soil Region”. Proceedings of Voronezh State University. Series: Geography. Geoecology0, no. 4 (December 9, 2021): 50-59. Accessed December 5, 2025. https://journals.vsu.ru/geo/article/view/3750.