Heiland, Frank, and Shirley Liu. 2006. “Family Structure and Wellbeing of Out-of-Wedlock Children: The Significance of the Biological Parents’ Relationship”. Demographic Research 15: 61-104. Referenced from www.demographic-research.org: Family Structure and Wellbeing of Out-of-Wedlock Children: The Significance of the Biological Parents’ Relationship.

Liu, Shirley, and Frank Heiland. 2010. “Should We Get Married? The Effect of Parents’ Marriage on Out-of-Wedlock Children”. Economic Inquiry 50 (1): 17-38. Referenced from onlinelibrary.wiley.com: Should We Get Married? The Effect of Parents’ Marriage on Out-of-Wedlock Children.

Liu, Shirley, and Frank Heiland. 2009. “New Estimates on the Effect of Parental Separation on Child Health”. In Causal Analysis in Population Studies: Concepts, Methods, Application, edited by Henriette Engelhardt, Hans-Peter Kohler, and Alexia Fürnkranz-Prskawetz, 167-99. Vienna: Springer. Referenced from link.springer.com: New Estimates on the Effect of Parental Separation on Child Health.