Moura, S. F., F. N. H. Ferreira, J. L. R. de Sousa, and V. M. R. Ponte. “The Value of the Intangible in Institutions of Higher Education: A Focus on Human Capital”. Review of Business Management, vol. 7, no. 18, July 2007, pp. 60-71, doi:10.7819/rbgn.v7i18.45.