1. Amaratunga, D., Baldry, D., Sarshar, M., & Newton, R. (2002). Quantitative and qualitative research in the built environment: application of “mixed” research approach. Work study, 51(1), 17–31.
2. Antoniu, E., & Isac, N. (2009). Human resources—essential factor in sustainable economic development. Agricultural Management/Lucrari Stiintifice Seria I, Management Agricol, 11(1).
3. Barro, R. J. (2001). Human capital and growth. American Economic Review, 91(2), 12–17.
4. Becker, G.S. (1975). Front matter, human capital: a theoretical and empirical analysis, with special reference to education. In Human Capital: A Theoretical and Empirical Analysis, with Special Reference to Education, Second (pp. 22). NBER.
5. Benbasat, I., Goldstein, D. K., & Mead, M. (1987). The case research strategy in studies of information systems. MIS Quarterly, 369–386.