WĘGRZYN, Grażyna. The Service Sector of a Knowledge-based Economy ? a Comparative Study. Oeconomia Copernicana, [S. l.], v. 4, n. 1, p. 53–64, 2013. DOI: 10.12775/OeC.2013.004. Disponível em: https://oeconomia.pl/index.php/oc/article/view/448. Acesso em: 21 jan. 2026.