RYKIEL, Zbigniew. European boundaries in spatial research. European Spatial Research and Policy, [S. l.], v. 2, n. 1, p. 35–47, 1995. DOI: 10.18778/1231-1952.2.1.03. Disponível em: https://czasopisma.uni.lodz.pl/esrap/article/view/24682. Acesso em: 30 mar. 2025.