PIETRZYKOWSKI, Maciej. Convergence in GDP per capita across the EU regions— spatial effects. Economics and Business Review, Poland, v. 5, n. 2, p. 64–85, 2019. DOI: 10.18559/ebr.2019.2.4. Disponível em: https://journals.ue.poznan.pl/ebr/article/view/361. Acesso em: 3 apr. 2025.