Stam, Erik, Chantal Hartog, André van Stel, and Roy Thurik. "Ambitious Entrepreneurship, High-Growth Firms, and Macroeconomic Growth." The Dynamics of Entrepreneurship: Evidence from Global Entrepreneurship Monitor Data. : Oxford University Press, 2011-07-01. Oxford Scholarship Online. 2011-09-22. Date Accessed 23 May. 2013 <http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780199580866.001.0001/acprof-9780199580866-chapter-11>.
Stam, E., Hartog, C., Stel, A., & Thurik, R.(2011-07-01). Ambitious Entrepreneurship, High-Growth Firms, and Macroeconomic Growth. In The Dynamics of Entrepreneurship: Evidence from Global Entrepreneurship Monitor Data. : Oxford University Press. Retrieved 23 May. 2013, from http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780199580866.001.0001/acprof-9780199580866-chapter-11.
Stam, Erik, Chantal Hartog, André van Stel, and Roy Thurik. "Ambitious Entrepreneurship, High-Growth Firms, and Macroeconomic Growth." In The Dynamics of Entrepreneurship: Evidence from Global Entrepreneurship Monitor Data. : Oxford University Press, 2011-07-01. http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780199580866.001.0001/acprof-9780199580866-chapter-11.
Stam E, Hartog C, Stel Av, Thurik R. Ambitious Entrepreneurship, High-Growth Firms, and Macroeconomic Growth. In: Minniti M. The Dynamics of Entrepreneurship: Evidence from Global Entrepreneurship Monitor Data. Oxford University Press; 2011. http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780199580866.001.0001/acprof-9780199580866-chapter-11. Accessed May 23, 2013.