1. Ainsworth, M., & Bell, S. (1970). Attachment, exploration, and separation: Illustrated by the behavior of one-year-olds in a strange situation. Child Development, 41, 49–67.
2. Ainsworth, M. D. S., Blehar, M. C., Waters, E., & Wall, S. N. (1978). Patterns of attachment: a psychological study of the strange situation. Hillsdale, Lawlence Erlbaum Associates.
3. Ainsworth, M. D. S., Blehar, M. C., Waters, E., & Wall, S. N. (2015). Patterns of attachment: A psychological study of the strange situation. London: Psychology Press.
4. Andangsari, E., Gumilar, I., & Godwin, R. (2013). Social networking sites uses and psychological attachment need among Indonesian young adults population. International Journal of Social Science Studies, 1, 133–138.
5. Andreassen, C. S., Torsheim, T., Brunborg, G. S., & Pallesen, S. (2012). Development of a Facebook addiction scale. Psychological Reports, 110(2), 501–517.