1. Aassve, A., Davia, M. A., Lacovou, M. & Mazzuco, S. (2005). Does leaving home make you poor? Evidence from 13 European countries’, ISER Working Paper 2005-24. Colchester: University of Essex.
2. When to control for covariates? Panel asymptotics for estimates of treatment effects;Angrist;The Review of Economics and Statistics,2004
3. Estimation of average treatment effects based on propensity scores;Becker;The STATA Journal,2002
4. The use of propensity score matching in the evaluation of active labour market policies;Bryson,2002
5. Caliendo, M. & Kopeinig, S. (2005). Some practical guidance for the implementation of propensity score matching, IZA working paper, number 1588, http://repec.iza.org/dp1588.pdf.