DORAN, J.; RYAN, G. The effectiveness of R&D and external interaction for innovation: Insights from quantile regression. Economic Issues, [S. l.], v. 21, n. 1, p. 47–65, 2016. Disponível em: https://mail.economicissues.org.uk/index.php/EI_OJS/article/view/253. Acesso em: 11 nov. 2026.