OPIOŁA, W. Border in the theory of borderlands. Border and Regional Studies, [S. l.], v. 2, n. 1, p. 35–43, 2014. DOI: 10.25167/ppbs621. Disponível em: https://czasopisma.uni.opole.pl/index.php/p/article/view/621. Acesso em: 4 aug. 2025.