KRAWCZYK, Marzena. Sources of Information for Innovative Activity of Enterprises. Types, Importance, Measurement. Oeconomia Copernicana, [S. l.], v. 4, n. 1, p. 5–18, 2013. DOI: 10.12775/OeC.2013.001. Disponível em: https://apcz.umk.pl/OeC/article/view/OeC.2013.001. Acesso em: 26 jun. 2026.