Heckman, J. J. (1999). Policies to foster human capital. National Bureau of Economic Research.
Chicago-viite (17. p.)Heckman, James J. Policies to Foster Human Capital. Cambridge: National Bureau of Economic Research, 1999.
MLA-viite (9. p.)Heckman, James J. Policies to Foster Human Capital. National Bureau of Economic Research, 1999.
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