Smirnova, Ol'ga P., and Alena O. Ponomareva. “Modelling Interregional Cooperation in the Real Sector of the Russian Economy”. Amazonia Investiga 8, no. 22 (September 26, 2019): 6–14. Accessed September 14, 2025. https://www.amazoniainvestiga.info/index.php/amazonia/article/view/15.