Duncan, G. J., & Sojourner, A. J. (2013). Can Intensive Early Childhood Intervention Programs Eliminate Income-Based Cognitive and Achievement Gaps? J Hum Resour.
Chicago-tyylinen lähdeviittausDuncan, Greg J., ja Aaron J. Sojourner. "Can Intensive Early Childhood Intervention Programs Eliminate Income-Based Cognitive and Achievement Gaps?" J Hum Resour 2013.
MLA-viiteDuncan, Greg J., ja Aaron J. Sojourner. "Can Intensive Early Childhood Intervention Programs Eliminate Income-Based Cognitive and Achievement Gaps?" J Hum Resour 2013.
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