1. Archibald, R., & Feldman, D. (2006). State higher education spending and the tax revolt. Journal of Higher Education, 77, 618–644.
2. Ashenfelter, O., & Krueger, A. (1994). Estimates of the economic return to schooling from a new sample of twins. American Economic Review, 84(5), 1157–1173.
3. Ashenfelter, O., & Rouse, C. (1998). Income, schooling, and ability: Evidence from a new sample of identical twins. Quarterly Journal of Economics, 113(1), 253–284.
4. Baltagi, B. H. (2008). Econometric analysis of panel data (4th ed.). Chichester: Wiley.
5. Becher, T., & Trowler, P. (2001). Academic tribes and territories: Intellectual enquiry and the cultures of disciplines. Buckingham: Society for Research in Higher Education/Open University Press.