Williams, Sonya, and Stephen Freedman (2010). The Employment Retention and Advancement project: Background characteristics and patterns of employment, earnings, and public assistance receipt of adults in two-parent families, Washington, DC: Office of Planning, Research, and Evaluation, Administration for Children and Families, U.S. Department of Health and Human Services. Available at https://www.mdrc.org/publication/background-characteristics-and-patterns-employment-earnings-and-public-assistance.