UMIŃSKI, Stanisław. Export performance cluster analysis of Poland’s regions in the first 20 years of EU membership. Quaestiones Geographicae, [S. l.], v. 44, n. 4, p. 31–41, 2025. DOI: 10.14746/quageo-2025-0040. Disponível em: https://pressto.amu.edu.pl/index.php/qg/article/view/51451. Acesso em: 8 jan. 2026.