MADEIRA, M. J.; CARVALHO, J.; MIGUEL MOREIRA, J. R.; DUARTE, F. A.; DE SÃO PEDRO FILHO, F. Barriers to Innovation and the Innovative Performance of Portuguese Firms. Journal of Business, Universidad del Pacífico (Lima, Peru), v. 9, n. 1, p. 2-22, 22 out. 2017.