Drapkin И. М., Mariev О. С., and Monastyrenko Е. К. “Foreign Direct Investment in the Economy With Vertical Linkages: A Model With Heterogeneous Firms”. Vestnik IzhGTU Imeni M.T. Kalashnikova, no. 4, Dec. 2013, pp. 89-92, https://izdat.istu.ru/index.php/vestnik/article/view/2734.