VASILY, V.; BILCHAK, M. Stratification Approach to Research Border Economy. Olsztyn Economic Journal, [S. l.], v. 9, n. 4, p. 305–320, 2014. DOI: 10.31648/oej.3183. Disponível em: https://czasopisma.uwm.edu.pl/index.php/oej/article/view/3183. Acesso em: 6 may. 2024.