DUDA, Natalia. The Ageing of Society and the Stability of the Retirement and Healthcare Systems in Poland. Olsztyn Economic Journal, [S. l.], v. 21, n. 2, p. 21–34, 2026. DOI: 10.31648/oej.13007. Disponível em: https://czasopisma.uwm.edu.pl/index.php/oej/article/view/13007. Acesso em: 15 nov. 2026.