TY - JOUR A1 - Li, H. A1 - Zhang, J. A1 - Zhu, Y. T1 - The Quantity-Quality Trade-off of Children in a Developing Country: Identification Using Chinese Twins Y1 - 2008 DO - 10.1353/dem.2008.0006 JF - Demography VL - 45 IS - 1 SP - 223 EP - -243 ER -