TRZEPACZ, Piotr. Spatial aspects of air transportation liberalization - changes in European airport hierarchy. Bulletin of Geography. Socio-economic Series, [S. l.], n. 8, p. 163–177, 2007. DOI: 10.1515/2438. Disponível em: https://apcz.umk.pl/BGSS/article/view/2438. Acesso em: 8 jul. 2025.