Polischuk Е. А., and Cheban А. В. “Theory of Externalities and Its Practical Application for Economic Practice”. Vestnik IzhGTU Imeni M.T. Kalashnikova, vol. 18, no. 1, Mar. 2015, pp. 45-47, https://izdat.istu.ru/index.php/vestnik/article/view/2073.