1. Aikens, N., Akers, L. & Atkins-Burnett, S. (2016). Professional development tools to improve the quality of infant and toddler care: A review of the literature (No 3faeb9b866d946cdaef275044b900ecc). Mathematica Policy Research.
2. The Bowlby-Ainsworth attachment theory
3. Bandel, E., Aikens, N., Vogel, C. A., Boller, K. & Murphy, L. (2014). Observed quality and psychometric properties of the CLASS-T in the early head start family and child experiences survey. Mathematica Policy Research.