1. Abbott, L., & Rodgers, R. (Eds.). (1994). Quality in the early years. Buckingham, UK: Open University Press.
2. Aboulafia, A. (1991). Social constructivism and social constructionism. In E. Axel, K. Baltzer, C.R. Hansen, & J. Mammen (Eds.), Virksomhed, viden, læring [Activity, knowledge, learning] (pp. 63–85). Aarhus, Denmark: Aarhus Universitetsforlag.
3. Ainsworth, M., & Witting, B. A. (1969). Attachment and exploratory behaviour of one-year-olds in a strange situation. In B. M. Foss (Ed.), Determinants of infant behaviour (Vol. 4, pp. 111–136). London: Methuen; New York: Barnes & Noble.
4. Bowlby, J. (1998). Attachment and loss (2nd ed.). London: Pilico.
5. Broström, S. (1995). Education, motivation for learning, and social competence of 6-year-olds in kindergarten in Denmark and the United States. Child & Youth Care Forum, 24(2), 107–123.