1. Acs, Z. J. (2002). Innovation and the growth of cities. Cheltenham: Edward Elgar.
2. Acs, Z. J., Audretsch, D. B., Braunerhjelm, P., & Carlson, B. (2004). The missing link the knowledge filter and entrepreneurship in endogenous growth. Working Paper 4783. London: Center for Economic Policy Research.
3. Acs, Z. J., Audretsch, D. B., Braunerhjelm, P., & Carlson, B. (2005). Growth and entrepreneurship: An empirical assessment. Working Paper 3205, Discussion papers on entrepreneurship, growth and public policy. Jena, Germany: Max Plank Institute of Economics.
4. Acs, Z. J., & Plummer, L. A. (2005). Penetrating the “knowledge filter’” in regional economies. The Annals of Regional Science, 39(3), 439–456.
5. Akehurst, G., Comeche, J. M., & Galindo, M. A. (2009). An approach to the influence of variables of attitude in the entrepreneurial SME. Small Business Economics, 32, 277–289.