TY  - JOUR
A1  - Heckman, J.J.
A1  - J.R., Walker.
T1  - The relationship between wages and income and the timing and spacing of births – evidence from Swedish longitudinal data
Y1  - 1990
DO  - 10.2307/2938322
JF  - Econometrica
VL  - 58
IS  - 6

ER  -