@conference {4680, title = {Research and Development expenditure in the business sector as indicator of knowledge economy: the Portuguese experience}, booktitle = {IET Working Papers Series}, year = {2007}, publisher = {FCT-UNL}, organization = {FCT-UNL}, address = {Caparica}, author = {Nuno Boavida and Ant{\'o}nio Brand{\~a}o Moniz} }