1. Bertrand, M.; Duflo, E.; Mullainathan, S. "How Much Should We Trust Differences-in-Differences Estimates?" The Quarterly Journal of Economics, v. 119, n. 1, p. 249-275, February 2004
2. Forfas: Profile of Employment and Unemployment, February 2010
3. Department of Numbers: Should We Classify GDP Recessions and Jobs Recessions Separately?
4. Institute for Employment Studies: The National Strategic Skills Audit for England 2010, Volume 1, Key Findings
5. Catherine Rampell (NYT): Want a Higher G.P.A.? Go to a Private College
6. Eurostat's Unemployment Statistics
7. Ronan Lyon's Rent-or-Buy Calculator