WYSZKOWSKA-KUNA, Joanna. Internal and External Sources of Knowledge in Manufacturing and Service Enterprises. A Comparative Analysis of European Union Countries. Comparative Economic Research. Central and Eastern Europe, [S. l.], v. 23, n. 3, p. 21–39, 2020. DOI: 10.18778/1508-2008.23.18. Disponível em: https://czasopisma.uni.lodz.pl/CER/article/view/8307. Acesso em: 8 dec. 2025.