1. Ainsworth, M. D. (1964). Patterns of attachment behavior shown by the infant in interaction with his mother. Merrill Palmer Quarterly, 10, 51–58.
2. Ainsworth, M. D. (1969). Object relations, dependency and attachment: A theoretical review of the infant-mother relationship. Child Development, 40, 969–1025.
3. Ainsworth, M.D., & Wittig, B.A. (1969). Attachment and exploratory behavior of one year olds in a strange situation. In B.M. Foss (Ed.), Determinants of Infant Behavior (Vol. 4). London: Methuen.
4. Bell, R. Q. (1968). A reinterpretation of the direction of effects in studies in socialization. Psychology Review, 75, 8–95.
5. Belsky, J. (1985). Day care reconsidered. Unpublished manuscript.